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  • Is it possible to define XML scheme with node names specified via regular expressions?

    - by MartyIX
    Hello, I know it is probably a question against XML philosophy but still is it possible to define scheme for XML like this: <Root> <arbitrary-name-of-node> <Name></Name> <Position></Position> <!-- ... --> </arbitrary-name-of-node> <arbitrary-name-of-node> <Name></Name> <Position></Position> <!-- ... --> </arbitrary-name-of-node> </Root> where arbitrary-name-of-node matches regular expression [a-zA-Z0-9]? Thanks for an answer!

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  • Can we use (id) in if- else condition ?

    - by srikanth rongali
    I have written my code in following way in cocos2d. id actionTo = [CCFadeOut actionWithDuration:4.0f]; id actionTo0 = [CCSequence actionWithDuration:2.0f]; if (m < enemyNumber) id actionTo1 = [CCCallFunc actionWithTarget:self selector:@selector(goToNextScene)]; else id actionTo1 = [CCCallFunc actionWithTarget:self selector:@selector(goToEndScene)]; id actionSeq = [CCSequence actions:actionTo, actionTo0, actionTo1, nil]; [targetE runAction: [CCSequence actions:actionSeq, nil]]; error: expected expression before 'id' I am getting the above error. Should not we use (id) in if condition ? I want to get called two selectors by using the if- else condition. How can I make it ? Thank You.

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  • Replace non-html links with <A> tags

    - by tombazza
    I have a block of code that will take a block of text like the following: Sample text sample text http://www.google.com sample text Using the preg_replace_callback method and the following regular expression: preg_replace_callback('/http:\/\/([,\%\w.\-_\/\?\=\+\&\~\#\$]+)/', create_function( '$matches', '$url = $matches[1]; $anchorText = ( strlen($url) > 35 ? substr($url, 0, 35).\'...\' : $url); return \'<a href="http://\'. $url .\'">\'. $anchorText .\'</a>\';'), $str); Will convert the sample text to look like: Sample text sample text < a href="http://www.google.com"http://www.google.com< /a sample text My problem now is that we have introduced a rich text editor that can create links before being sent to the script. I need to update this piece of code so that it will ignore any URLs that are already inside an tag.

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  • @ symbol for strings in jQuery

    - by anilca
    if (confirm('<%=Ns1.Ns2.MyClass.GetResourceText("DeleteConfirmationMessage")%>')) { /* something to do...*/ } I have a jQuery expression as above. But the return value of GetResourceText method is a very long string. So my page renders the function like below: if (confirm(' Are you sure lablabla? If you delete this lablabla... lablabla... ')) { Because of this my jQuery functions do not work. Is there a symbol for jQuery like @ that we use in C#?

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  • Some pro regular expressions help needed here

    - by Camran
    I need a special regular expression, have no experience in them whatsoever so I am turning to you guys on this one: I need to validate a classifieds title field so it doesn't have any special characters in it, almost. Only letters and numbers should be allowed, and also the swedish three letters å, ä, ö, and also not case sensitive. Besides the above, these should also be allowed: The "&" sign. Parenthesis sign "()" Mathematical signs "-", "+", "%", "/", "*" Dollar and Euro signs Accent sign or whatever it's called, for example in "coupé" the apostrophe above the "e". Double quote and singel quote signs. The comma "," and point "." signs Thanks

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  • C# Why does calling an interface member from a class generate an error?

    - by Jack
    So I have an interface: interface IFoo { int Bar(); int this[int i] {get; set;} } And a class that derives from it class Foo : IFoo { public int IFoo.Bar() { //Implementation { public int IFoo.this[int i] { //Implementation } } Now, I try to do this: var fooey = new Foo(); int i = Fooey.Bar(); or this: int i = Fooey[4]; I would expect these to work properly. However, the compiler generates an error as if such members don't exist. Why is that? I am aware I can cast Foo as IFoo, but I am also aware that casting is costly to performance, which is often the reason to use interfaces in the first place. EDIT 1: These are the errors generated 'Foo' does not contain a definition for 'Bar' and no extension method 'Bar' accepting a first argument of type 'Foo' could be found (are you missing a using directive or an assembly reference?) "Cannot apply indexing to an expression of type 'Foo'"

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  • Using sed with html data

    - by StackedCrooked
    I'm having some problems using sed in combination with html. The following sample illustrates the problem: HTML="<html><body>ENTRY</body><html>" TABLE="<table></table>" echo $HTML | sed -e s/ENTRY/$TABLE/ This outputs: sed: -e expression #1, char 18: unknown option to `s' If I leave out the / from $TABLE so that it becomes <table><table> it works ok. Any ideas on how to fix it?

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  • .NET regex inner text between td, span, a tag

    - by mushtaqck
    <table > <tr> <td colspan="2" style="height: 14px"> tdtext1 <a>hyperlinktext1<a/> </td> </tr> <tr> <td> tdtext2 </td> <td> <span>spantext1</span> </td> </tr> </table> This is my sample text how to write a regular expression in C# to get the matches for the innertext for td, span, hyperlinks.

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  • Does '[ab]+' equal '(a|b)+' in python re module?

    - by user1477871
    I think pat1 = '[ab]' and pat2 = 'a|b' have the same function in Python(python2.7, windows) 're' module as a regular expression pattern. But I am confused with '[ab]+' and '(a|b)+', do they have the same function, if not plz explain details. ''' Created on 2012-9-4 @author: melo ''' import re pat1 = '(a|b)+' pat2 = '[ab]+' text = '22ababbbaa33aaa44b55bb66abaa77babab88' m1 = re.search(pat1, text) m2 = re.search(pat2, text) print 'search with pat1:', m1.group() print 'search with pat2:', m2.group() m11 = re.split(pat1, text) m22 = re.split(pat2, text) print 'split with pat1:', m11 print 'split with pat2:', m22 m111 = re.findall(pat1, text) m222 = re.findall(pat2, text) print 'findall with pat1:', m111 print 'findall with pat2:', m222 output as below: search with pat1: ababbbaa search with pat2: ababbbaa split with pat1: ['22', 'a', '33', 'a', '44', 'b', '55', 'b', '66', 'a', '77', 'b', '88'] split with pat2: ['22', '33', '44', '55', '66', '77', '88'] findall with pat1: ['a', 'a', 'b', 'b', 'a', 'b'] findall with pat2: ['ababbbaa', 'aaa', 'b', 'bb', 'abaa', 'babab'] why are 'pat1' and 'pat2' different and what's their difference? what kind of strings can 'pat1' actually match?

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  • cron library for java

    - by nutsiepully
    I am looking for a cron expression library in java. Something that can parse cron expressions and return me future fire times for the trigger. API on the lines of. CronExpression cronExpression = new CronExpression("0 30 4 * * *"); List<Date> fireTimes = cronExpression.getFireTimes(todaysDate, nextWeekDate); I don't want to use something as complicated as quartz. The purpose is to basically use cron like a regex for timings. That's all. I do not want a background scheduler. I tried googling but wasn't able to find anything very helpful. Any suggestions would be appreciated. Regards, Pulkit P.S - I looked at using the CronExpression class out of quartz. Wasn't very helpful - failing some tests.

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  • How can I get the file extensions from relative links in HTML text using Perl?

    - by Structure
    For example, scanning the contents of an HTML page with a Perl regular expression, I want to match all file extensions but not TLD's in domain names. To do this I am making the assumption that all file extensions must be within double quotes. I came up with the following, and it is working, however, I am failing to figure out a way to exclude the TLDs in the domains. This will return "com", "net", etc. m/"[^<>]+\.([0-9A-Za-z]*)"/g Is it possible to negate the match if there is more than one period between the quotes that are separated by text? (ie: match foo.bar.com but not ./ or ../) Edit I am using $1 to return the value within parentheses.

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  • Dereferencing confusion? What is this example here called?

    - by perf
    Considering this PHP example: class A { public function getB( ) { return new B(); } } class B { public function test( ) { echo "Hello"; } } I could use this: $a = new A( ); $b = $a->getB( ); $b->test( ); // Hello Or this: $a = new A(); $a->getB( )->test( ); // Hello Taking a closer look at the second example... What is the name of this form of expression? Does this have something to do with dereferencing? In which programming languages is this available? What other forms of this exist?

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  • aspx page with gridview runs very fast in IE but 20% of the speed on Firefox

    - by frank2009
    Hi there I have a simple aspx page with some search options which queries an SQLEXpress database, and it is displayed in a gridview. For some reason, it runs lightning fast in IE but very slow in Firefox. It has very little code, a gridview a couple of images and a couple of textboxes and a search button. It was done with Expression Web so no additional code added. In production (not local) the speed is very noticiable when doing a search... IE displays the results almost instantly...Firefox might take 3-5 seconds. And everything else runs super fast as well in IE (update, delete etc). Is there a reason for this ? Thanks

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  • Silverlight hangs at 100% loaded.

    - by Spines
    My Silverlight website hangs at 100% loaded. There is no code for it, so far it is just the design in XAML, and it shows up fine in Expression Blend 3. It is the standard "Silverlight Website" project from Blend 3, without any modifications. When I press F5 to run it, it shows as a 100% loading circle in firefox and never actually shows my app. The loading circle continues to animate as if its doing something. Note: It worked yesterday, and I havent made very many changes to it since then.

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  • Troubleshoot Perl module installation on Mac OS X

    - by Daniel Standage
    I'm trying to install the Perl module Set::IntervalTree on Mac OS X. I recently installed it today on an Ubuntu box with no problem. I simply started cpan, entered install Set:IntervalTree, and it all worked out. However, the installation failed on Mac OS X--it spits out a huge list of compiler errors (below). How would I troubleshoot this. I don't even know where to begin. cpan[1]> install Set::IntervalTree CPAN: Storable loaded ok (v2.18) Going to read /Users/standage/.cpan/Metadata Database was generated on Fri, 14 Jan 2011 02:58:42 GMT CPAN: YAML loaded ok (v0.72) Going to read /Users/standage/.cpan/build/ ............................................................................DONE Found 1 old build, restored the state of 1 Running install for module 'Set::IntervalTree' Running make for B/BE/BENBOOTH/Set-IntervalTree-0.01.tar.gz CPAN: Digest::SHA loaded ok (v5.45) CPAN: Compress::Zlib loaded ok (v2.008) Checksum for /Users/standage/.cpan/sources/authors/id/B/BE/BENBOOTH/Set-IntervalTree-0.01.tar.gz ok Scanning cache /Users/standage/.cpan/build for sizes ............................................................................DONE x Set-IntervalTree-0.01/ x Set-IntervalTree-0.01/src/ x Set-IntervalTree-0.01/src/Makefile x Set-IntervalTree-0.01/src/interval_tree.h x Set-IntervalTree-0.01/src/test_main.cc x Set-IntervalTree-0.01/lib/ x Set-IntervalTree-0.01/lib/Set/ x Set-IntervalTree-0.01/lib/Set/IntervalTree.pm x Set-IntervalTree-0.01/Changes x Set-IntervalTree-0.01/MANIFEST x Set-IntervalTree-0.01/t/ x Set-IntervalTree-0.01/t/Set-IntervalTree.t x Set-IntervalTree-0.01/typemap x Set-IntervalTree-0.01/perlobject.map x Set-IntervalTree-0.01/IntervalTree.xs x Set-IntervalTree-0.01/Makefile.PL x Set-IntervalTree-0.01/README x Set-IntervalTree-0.01/META.yml CPAN: File::Temp loaded ok (v0.18) CPAN.pm: Going to build B/BE/BENBOOTH/Set-IntervalTree-0.01.tar.gz Checking if your kit is complete... Looks good Writing Makefile for Set::IntervalTree cp lib/Set/IntervalTree.pm blib/lib/Set/IntervalTree.pm AutoSplitting blib/lib/Set/IntervalTree.pm (blib/lib/auto/Set/IntervalTree) /usr/bin/perl /System/Library/Perl/5.10.0/ExtUtils/xsubpp -C++ -typemap /System/Library/Perl/5.10.0/ExtUtils/typemap -typemap perlobject.map -typemap typemap IntervalTree.xs > IntervalTree.xsc && mv IntervalTree.xsc IntervalTree.c g++ -c -Isrc -arch x86_64 -arch i386 -arch ppc -g -pipe -fno-common -DPERL_DARWIN -fno-strict-aliasing -I/usr/local/include -g -O0 -DVERSION=\"0.01\" -DXS_VERSION=\"0.01\" "-I/System/Library/Perl/5.10.0/darwin-thread-multi-2level/CORE" -Isrc IntervalTree.c In file included from /usr/include/c++/4.2.1/bits/basic_ios.h:44, from /usr/include/c++/4.2.1/ios:50, from /usr/include/c++/4.2.1/ostream:45, from /usr/include/c++/4.2.1/iostream:45, from IntervalTree.xs:16: /usr/include/c++/4.2.1/bits/locale_facets.h:4420:40: error: macro "do_open" requires 7 arguments, but only 2 given /usr/include/c++/4.2.1/bits/locale_facets.h:4467:34: error: macro "do_close" requires 2 arguments, but only 1 given /usr/include/c++/4.2.1/bits/locale_facets.h:4486:55: error: macro "do_open" requires 7 arguments, but only 2 given /usr/include/c++/4.2.1/bits/locale_facets.h:4513:23: error: macro "do_close" requires 2 arguments, but only 1 given In file included from /usr/include/c++/4.2.1/bits/locale_facets.h:4599, from /usr/include/c++/4.2.1/bits/basic_ios.h:44, from /usr/include/c++/4.2.1/ios:50, from /usr/include/c++/4.2.1/ostream:45, from /usr/include/c++/4.2.1/iostream:45, from IntervalTree.xs:16: /usr/include/c++/4.2.1/i686-apple-darwin10/x86_64/bits/messages_members.h:58:38: error: macro "do_open" requires 7 arguments, but only 2 given /usr/include/c++/4.2.1/i686-apple-darwin10/x86_64/bits/messages_members.h:67:71: error: macro "do_open" requires 7 arguments, but only 2 given /usr/include/c++/4.2.1/i686-apple-darwin10/x86_64/bits/messages_members.h:78:39: error: macro "do_close" requires 2 arguments, but only 1 given In file included from /usr/include/c++/4.2.1/bits/basic_ios.h:44, from /usr/include/c++/4.2.1/ios:50, from /usr/include/c++/4.2.1/ostream:45, from /usr/include/c++/4.2.1/iostream:45, from IntervalTree.xs:16: /usr/include/c++/4.2.1/bits/locale_facets.h:4486: error: ‘do_open’ declared as a ‘virtual’ field /usr/include/c++/4.2.1/bits/locale_facets.h:4486: error: expected ‘;’ before ‘const’ /usr/include/c++/4.2.1/bits/locale_facets.h:4513: error: variable or field ‘do_close’ declared void /usr/include/c++/4.2.1/bits/locale_facets.h:4513: error: expected ‘;’ before ‘const’ In file included from /usr/include/c++/4.2.1/bits/locale_facets.h:4599, from /usr/include/c++/4.2.1/bits/basic_ios.h:44, from /usr/include/c++/4.2.1/ios:50, from /usr/include/c++/4.2.1/ostream:45, from /usr/include/c++/4.2.1/iostream:45, from IntervalTree.xs:16: /usr/include/c++/4.2.1/i686-apple-darwin10/x86_64/bits/messages_members.h:67: error: expected initializer before ‘const’ /usr/include/c++/4.2.1/i686-apple-darwin10/x86_64/bits/messages_members.h:78: error: expected initializer before ‘const’ In file included from IntervalTree.xs:19: src/interval_tree.h:95: error: type/value mismatch at argument 1 in template parameter list for ‘template<class _Tp, class _Alloc> class std::vector’ src/interval_tree.h:95: error: expected a type, got ‘IntervalTree<T,N>::it_recursion_node’ src/interval_tree.h:95: error: template argument 2 is invalid src/interval_tree.h: In constructor ‘IntervalTree<T, N>::IntervalTree()’: src/interval_tree.h:130: error: expected type-specifier src/interval_tree.h:130: error: expected `;' src/interval_tree.h:135: error: expected type-specifier src/interval_tree.h:135: error: expected `;' src/interval_tree.h:141: error: request for member ‘push_back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h: In member function ‘void IntervalTree<T, N>::LeftRotate(IntervalTree<T, N>::Node*)’: src/interval_tree.h:178: error: ‘y’ was not declared in this scope src/interval_tree.h: In member function ‘void IntervalTree<T, N>::RightRotate(IntervalTree<T, N>::Node*)’: src/interval_tree.h:240: error: ‘x’ was not declared in this scope src/interval_tree.h: In member function ‘void IntervalTree<T, N>::TreeInsertHelp(IntervalTree<T, N>::Node*)’: src/interval_tree.h:298: error: ‘x’ was not declared in this scope src/interval_tree.h:299: error: ‘y’ was not declared in this scope src/interval_tree.h: In member function ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::insert(const T&, N, N)’: src/interval_tree.h:375: error: ‘y’ was not declared in this scope src/interval_tree.h:376: error: ‘x’ was not declared in this scope src/interval_tree.h:377: error: ‘newNode’ was not declared in this scope src/interval_tree.h:379: error: expected type-specifier src/interval_tree.h:379: error: expected `;' src/interval_tree.h: In member function ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::GetSuccessorOf(IntervalTree<T, N>::Node*) const’: src/interval_tree.h:450: error: ‘y’ was not declared in this scope src/interval_tree.h: In member function ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::GetPredecessorOf(IntervalTree<T, N>::Node*) const’: src/interval_tree.h:483: error: ‘y’ was not declared in this scope src/interval_tree.h: In destructor ‘IntervalTree<T, N>::~IntervalTree()’: src/interval_tree.h:546: error: ‘x’ was not declared in this scope src/interval_tree.h:547: error: type/value mismatch at argument 1 in template parameter list for ‘template<class _Tp, class _Alloc> class std::vector’ src/interval_tree.h:547: error: expected a type, got ‘(IntervalTree<T,N>::Node * <expression error>)’ src/interval_tree.h:547: error: template argument 2 is invalid src/interval_tree.h:547: error: invalid type in declaration before ‘;’ token src/interval_tree.h:551: error: request for member ‘push_back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:554: error: request for member ‘push_back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:557: error: request for member ‘empty’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:558: error: request for member ‘back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:559: error: request for member ‘pop_back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:561: error: request for member ‘push_back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h:564: error: request for member ‘push_back’ in ‘stuffToFree’, which is of non-class type ‘int’ src/interval_tree.h: In member function ‘void IntervalTree<T, N>::DeleteFixUp(IntervalTree<T, N>::Node*)’: src/interval_tree.h:613: error: ‘w’ was not declared in this scope src/interval_tree.h:614: error: ‘rootLeft’ was not declared in this scope src/interval_tree.h: In member function ‘T IntervalTree<T, N>::remove(IntervalTree<T, N>::Node*)’: src/interval_tree.h:697: error: ‘y’ was not declared in this scope src/interval_tree.h:698: error: ‘x’ was not declared in this scope src/interval_tree.h: In member function ‘std::vector<T, std::allocator<_CharT> > IntervalTree<T, N>::fetch(N, N)’: src/interval_tree.h:819: error: ‘x’ was not declared in this scope src/interval_tree.h:833: error: invalid types ‘int[size_t]’ for array subscript src/interval_tree.h:836: error: request for member ‘push_back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:837: error: request for member ‘back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:838: error: request for member ‘back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:839: error: request for member ‘back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:840: error: request for member ‘size’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:846: error: request for member ‘size’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:847: error: expected `;' before ‘back’ src/interval_tree.h:848: error: request for member ‘pop_back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:850: error: ‘back’ was not declared in this scope src/interval_tree.h:853: error: invalid types ‘int[size_t]’ for array subscript IntervalTree.c: In function ‘void boot_Set__IntervalTree(PerlInterpreter*, CV*)’: IntervalTree.c:365: warning: deprecated conversion from string constant to ‘char*’ src/interval_tree.h: In constructor ‘IntervalTree<T, N>::IntervalTree() [with T = std::tr1::shared_ptr<sv>, N = long int]’: IntervalTree.c:67: instantiated from here src/interval_tree.h:130: error: cannot convert ‘int*’ to ‘IntervalTree<std::tr1::shared_ptr<sv>, long int>::Node*’ in assignment src/interval_tree.h:135: error: cannot convert ‘int*’ to ‘IntervalTree<std::tr1::shared_ptr<sv>, long int>::Node*’ in assignment ...blah blah blah... ...blah blah blah... ...blah blah blah... ...blah blah blah... ...blah blah blah... ...blah blah blah... src/interval_tree.h:848: error: request for member ‘pop_back’ in ‘((IntervalTree<T, N>*)this)->IntervalTree<T, N>::recursionNodeStack’, which is of non-class type ‘int’ src/interval_tree.h:850: error: ‘back’ was not declared in this scope src/interval_tree.h:853: error: invalid types ‘int[size_t]’ for array subscript IntervalTree.c: In function ‘void boot_Set__IntervalTree(PerlInterpreter*, CV*)’: IntervalTree.c:365: warning: deprecated conversion from string constant to ‘char*’ src/interval_tree.h: In constructor ‘IntervalTree<T, N>::IntervalTree() [with T = std::tr1::shared_ptr<sv>, N = long int]’: IntervalTree.c:67: instantiated from here src/interval_tree.h:130: error: cannot convert ‘int*’ to ‘IntervalTree<std::tr1::shared_ptr<sv>, long int>::Node*’ in assignment src/interval_tree.h:135: error: cannot convert ‘int*’ to ‘IntervalTree<std::tr1::shared_ptr<sv>, long int>::Node*’ in assignment src/interval_tree.h: In member function ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::insert(const T&, N, N) [with T = std::tr1::shared_ptr<sv>, N = long int]’: IntervalTree.xs:57: instantiated from here src/interval_tree.h:375: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:375: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h:376: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:376: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h:377: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:377: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h: In member function ‘std::vector<T, std::allocator<_CharT> > IntervalTree<T, N>::fetch(N, N) [with T = std::tr1::shared_ptr<sv>, N = long int]’: IntervalTree.xs:65: instantiated from here src/interval_tree.h:819: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:819: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant IntervalTree.xs:65: instantiated from here src/interval_tree.h:847: error: dependent-name ‘IntervalTree<T,N>::it_recursion_node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:847: note: say ‘typename IntervalTree<T,N>::it_recursion_node’ if a type is meant src/interval_tree.h: In destructor ‘IntervalTree<T, N>::~IntervalTree() [with T = std::tr1::shared_ptr<sv>, N = long int]’: IntervalTree.c:205: instantiated from here src/interval_tree.h:546: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:546: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h: In member function ‘void IntervalTree<T, N>::TreeInsertHelp(IntervalTree<T, N>::Node*) [with T = std::tr1::shared_ptr<sv>, N = long int]’: src/interval_tree.h:380: instantiated from ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::insert(const T&, N, N) [with T = std::tr1::shared_ptr<sv>, N = long int]’ IntervalTree.xs:57: instantiated from here src/interval_tree.h:298: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:298: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h:299: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:299: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h: In member function ‘void IntervalTree<T, N>::LeftRotate(IntervalTree<T, N>::Node*) [with T = std::tr1::shared_ptr<sv>, N = long int]’: src/interval_tree.h:395: instantiated from ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::insert(const T&, N, N) [with T = std::tr1::shared_ptr<sv>, N = long int]’ IntervalTree.xs:57: instantiated from here src/interval_tree.h:178: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:178: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant src/interval_tree.h: In member function ‘void IntervalTree<T, N>::RightRotate(IntervalTree<T, N>::Node*) [with T = std::tr1::shared_ptr<sv>, N = long int]’: src/interval_tree.h:399: instantiated from ‘typename IntervalTree<T, N>::Node* IntervalTree<T, N>::insert(const T&, N, N) [with T = std::tr1::shared_ptr<sv>, N = long int]’ IntervalTree.xs:57: instantiated from here src/interval_tree.h:240: error: dependent-name ‘IntervalTree<T,N>::Node’ is parsed as a non-type, but instantiation yields a type src/interval_tree.h:240: note: say ‘typename IntervalTree<T,N>::Node’ if a type is meant lipo: can't open input file: /var/tmp//ccLthuaw.out (No such file or directory) make: *** [IntervalTree.o] Error 1 BENBOOTH/Set-IntervalTree-0.01.tar.gz make -- NOT OK Running make test Can't test without successful make Running make install Make had returned bad status, install seems impossible Failed during this command: BENBOOTH/Set-IntervalTree-0.01.tar.gz : make NO

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  • Microsoft and jQuery

    - by Rick Strahl
    The jQuery JavaScript library has been steadily getting more popular and with recent developments from Microsoft, jQuery is also getting ever more exposure on the ASP.NET platform including now directly from Microsoft. jQuery is a light weight, open source DOM manipulation library for JavaScript that has changed how many developers think about JavaScript. You can download it and find more information on jQuery on www.jquery.com. For me jQuery has had a huge impact on how I develop Web applications and was probably the main reason I went from dreading to do JavaScript development to actually looking forward to implementing client side JavaScript functionality. It has also had a profound impact on my JavaScript skill level for me by seeing how the library accomplishes things (and often reviewing the terse but excellent source code). jQuery made an uncomfortable development platform (JavaScript + DOM) a joy to work on. Although jQuery is by no means the only JavaScript library out there, its ease of use, small size, huge community of plug-ins and pure usefulness has made it easily the most popular JavaScript library available today. As a long time jQuery user, I’ve been excited to see the developments from Microsoft that are bringing jQuery to more ASP.NET developers and providing more integration with jQuery for ASP.NET’s core features rather than relying on the ASP.NET AJAX library. Microsoft and jQuery – making Friends jQuery is an open source project but in the last couple of years Microsoft has really thrown its weight behind supporting this open source library as a supported component on the Microsoft platform. When I say supported I literally mean supported: Microsoft now offers actual tech support for jQuery as part of their Product Support Services (PSS) as jQuery integration has become part of several of the ASP.NET toolkits and ships in several of the default Web project templates in Visual Studio 2010. The ASP.NET MVC 3 framework (still in Beta) also uses jQuery for a variety of client side support features including client side validation and we can look forward toward more integration of client side functionality via jQuery in both MVC and WebForms in the future. In other words jQuery is becoming an optional but included component of the ASP.NET platform. PSS support means that support staff will answer jQuery related support questions as part of any support incidents related to ASP.NET which provides some piece of mind to some corporate development shops that require end to end support from Microsoft. In addition to including jQuery and supporting it, Microsoft has also been getting involved in providing development resources for extending jQuery’s functionality via plug-ins. Microsoft’s last version of the Microsoft Ajax Library – which is the successor to the native ASP.NET AJAX Library – included some really cool functionality for client templates, databinding and localization. As it turns out Microsoft has rebuilt most of that functionality using jQuery as the base API and provided jQuery plug-ins of these components. Very recently these three plug-ins were submitted and have been approved for inclusion in the official jQuery plug-in repository and been taken over by the jQuery team for further improvements and maintenance. Even more surprising: The jQuery-templates component has actually been approved for inclusion in the next major update of the jQuery core in jQuery V1.5, which means it will become a native feature that doesn’t require additional script files to be loaded. Imagine this – an open source contribution from Microsoft that has been accepted into a major open source project for a core feature improvement. Microsoft has come a long way indeed! What the Microsoft Involvement with jQuery means to you For Microsoft jQuery support is a strategic decision that affects their direction in client side development, but nothing stopped you from using jQuery in your applications prior to Microsoft’s official backing and in fact a large chunk of developers did so readily prior to Microsoft’s announcement. Official support from Microsoft brings a few benefits to developers however. jQuery support in Visual Studio 2010 means built-in support for jQuery IntelliSense, automatically added jQuery scripts in many projects types and a common base for client side functionality that actually uses what most developers are already using. If you have already been using jQuery and were worried about straying from the Microsoft line and their internal Microsoft Ajax Library – worry no more. With official support and the change in direction towards jQuery Microsoft is now following along what most in the ASP.NET community had already been doing by using jQuery, which is likely the reason for Microsoft’s shift in direction in the first place. ASP.NET AJAX and the Microsoft AJAX Library weren’t bad technology – there was tons of useful functionality buried in these libraries. However, these libraries never got off the ground, mainly because early incarnations were squarely aimed at control/component developers rather than application developers. For all the functionality that these controls provided for control developers they lacked in useful and easily usable application developer functionality that was easily accessible in day to day client side development. The result was that even though Microsoft shipped support for these tools in the box (in .NET 3.5 and 4.0), other than for the internal support in ASP.NET for things like the UpdatePanel and the ASP.NET AJAX Control Toolkit as well as some third party vendors, the Microsoft client libraries were largely ignored by the developer community opening the door for other client side solutions. Microsoft seems to be acknowledging developer choice in this case: Many more developers were going down the jQuery path rather than using the Microsoft built libraries and there seems to be little sense in continuing development of a technology that largely goes unused by the majority of developers. Kudos for Microsoft for recognizing this and gracefully changing directions. Note that even though there will be no further development in the Microsoft client libraries they will continue to be supported so if you’re using them in your applications there’s no reason to start running for the exit in a panic and start re-writing everything with jQuery. Although that might be a reasonable choice in some cases, jQuery and the Microsoft libraries work well side by side so that you can leave existing solutions untouched even as you enhance them with jQuery. The Microsoft jQuery Plug-ins – Solid Core Features One of the most interesting developments in Microsoft’s embracing of jQuery is that Microsoft has started contributing to jQuery via standard mechanism set for jQuery developers: By submitting plug-ins. Microsoft took some of the nicest new features of the unpublished Microsoft Ajax Client Library and re-wrote these components for jQuery and then submitted them as plug-ins to the jQuery plug-in repository. Accepted plug-ins get taken over by the jQuery team and that’s exactly what happened with the three plug-ins submitted by Microsoft with the templating plug-in even getting slated to be published as part of the jQuery core in the next major release (1.5). The following plug-ins are provided by Microsoft: jQuery Templates – a client side template rendering engine jQuery Data Link – a client side databinder that can synchronize changes without code jQuery Globalization – provides formatting and conversion features for dates and numbers The first two are ports of functionality that was slated for the Microsoft Ajax Library while functionality for the globalization library provides functionality that was already found in the original ASP.NET AJAX library. To me all three plug-ins address a pressing need in client side applications and provide functionality I’ve previously used in other incarnations, but with more complete implementations. Let’s take a close look at these plug-ins. jQuery Templates http://api.jquery.com/category/plugins/templates/ Client side templating is a key component for building rich JavaScript applications in the browser. Templating on the client lets you avoid from manually creating markup by creating DOM nodes and injecting them individually into the document via code. Rather you can create markup templates – similar to the way you create classic ASP server markup – and merge data into these templates to render HTML which you can then inject into the document or replace existing content with. Output from templates are rendered as a jQuery matched set and can then be easily inserted into the document as needed. Templating is key to minimize client side code and reduce repeated code for rendering logic. Instead a single template can be used in many places for updating and adding content to existing pages. Further if you build pure AJAX interfaces that rely entirely on client rendering of the initial page content, templates allow you to a use a single markup template to handle all rendering of each specific HTML section/element. I’ve used a number of different client rendering template engines with jQuery in the past including jTemplates (a PHP style templating engine) and a modified version of John Resig’s MicroTemplating engine which I built into my own set of libraries because it’s such a commonly used feature in my client side applications. jQuery templates adds a much richer templating model that allows for sub-templates and access to the data items. Like John Resig’s original Micro Template engine, the core basics of the templating engine create JavaScript code which means that templates can include JavaScript code. To give you a basic idea of how templates work imagine I have an application that downloads a set of stock quotes based on a symbol list then displays them in the document. To do this you can create an ‘item’ template that describes how each of the quotes is renderd as a template inside of the document: <script id="stockTemplate" type="text/x-jquery-tmpl"> <div id="divStockQuote" class="errordisplay" style="width: 500px;"> <div class="label">Company:</div><div><b>${Company}(${Symbol})</b></div> <div class="label">Last Price:</div><div>${LastPrice}</div> <div class="label">Net Change:</div><div> {{if NetChange > 0}} <b style="color:green" >${NetChange}</b> {{else}} <b style="color:red" >${NetChange}</b> {{/if}} </div> <div class="label">Last Update:</div><div>${LastQuoteTimeString}</div> </div> </script> The ‘template’ is little more than HTML with some markup expressions inside of it that define the template language. Notice the embedded ${} expressions which reference data from the quote objects returned from an AJAX call on the server. You can embed any JavaScript or value expression in these template expressions. There are also a number of structural commands like {{if}} and {{each}} that provide for rudimentary logic inside of your templates as well as commands ({{tmpl}} and {{wrap}}) for nesting templates. You can find more about the full set of markup expressions available in the documentation. To load up this data you can use code like the following: <script type="text/javascript"> //var Proxy = new ServiceProxy("../PageMethods/PageMethodsService.asmx/"); $(document).ready(function () { $("#btnGetQuotes").click(GetQuotes); }); function GetQuotes() { var symbols = $("#txtSymbols").val().split(","); $.ajax({ url: "../PageMethods/PageMethodsService.asmx/GetStockQuotes", data: JSON.stringify({ symbols: symbols }), // parameter map type: "POST", // data has to be POSTed contentType: "application/json", timeout: 10000, dataType: "json", success: function (result) { var quotes = result.d; var jEl = $("#stockTemplate").tmpl(quotes); $("#quoteDisplay").empty().append(jEl); }, error: function (xhr, status) { alert(status + "\r\n" + xhr.responseText); } }); }; </script> In this case an ASMX AJAX service is called to retrieve the stock quotes. The service returns an array of quote objects. The result is returned as an object with the .d property (in Microsoft service style) that returns the actual array of quotes. The template is applied with: var jEl = $("#stockTemplate").tmpl(quotes); which selects the template script tag and uses the .tmpl() function to apply the data to it. The result is a jQuery matched set of elements that can then be appended to the quote display element in the page. The template is merged against an array in this example. When the result is an array the template is automatically applied to each each array item. If you pass a single data item – like say a stock quote – the template works exactly the same way but is applied only once. Templates also have access to a $data item which provides the current data item and information about the tempalte that is currently executing. This makes it possible to keep context within the context of the template itself and also to pass context from a parent template to a child template which is very powerful. Templates can be evaluated by using the template selector and calling the .tmpl() function on the jQuery matched set as shown above or you can use the static $.tmpl() function to provide a template as a string. This allows you to dynamically create templates in code or – more likely – to load templates from the server via AJAX calls. In short there are options The above shows off some of the basics, but there’s much for functionality available in the template engine. Check the documentation link for more information and links to additional examples. The plug-in download also comes with a number of examples that demonstrate functionality. jQuery templates will become a native component in jQuery Core 1.5, so it’s definitely worthwhile checking out the engine today and get familiar with this interface. As much as I’m stoked about templating becoming part of the jQuery core because it’s such an integral part of many applications, there are also a couple shortcomings in the current incarnation: Lack of Error Handling Currently if you embed an expression that is invalid it’s simply not rendered. There’s no error rendered into the template nor do the various  template functions throw errors which leaves finding of bugs as a runtime exercise. I would like some mechanism – optional if possible – to be able to get error info of what is failing in a template when it’s rendered. No String Output Templates are always rendered into a jQuery matched set and there’s no way that I can see to directly render to a string. String output can be useful for debugging as well as opening up templating for creating non-HTML string output. Limited JavaScript Access Unlike John Resig’s original MicroTemplating Engine which was entirely based on JavaScript code generation these templates are limited to a few structured commands that can ‘execute’. There’s no code execution inside of script code which means you’re limited to calling expressions available in global objects or the data item passed in. This may or may not be a big deal depending on the complexity of your template logic. Error handling has been discussed quite a bit and it’s likely there will be some solution to that particualar issue by the time jQuery templates ship. The others are relatively minor issues but something to think about anyway. jQuery Data Link http://api.jquery.com/category/plugins/data-link/ jQuery Data Link provides the ability to do two-way data binding between input controls and an underlying object’s properties. The typical scenario is linking a textbox to a property of an object and have the object updated when the text in the textbox is changed and have the textbox change when the value in the object or the entire object changes. The plug-in also supports converter functions that can be applied to provide the conversion logic from string to some other value typically necessary for mapping things like textbox string input to say a number property and potentially applying additional formatting and calculations. In theory this sounds great, however in reality this plug-in has some serious usability issues. Using the plug-in you can do things like the following to bind data: person = { firstName: "rick", lastName: "strahl"}; $(document).ready( function() { // provide for two-way linking of inputs $("form").link(person); // bind to non-input elements explicitly $("#objFirst").link(person, { firstName: { name: "objFirst", convertBack: function (value, source, target) { $(target).text(value); } } }); $("#objLast").link(person, { lastName: { name: "objLast", convertBack: function (value, source, target) { $(target).text(value); } } }); }); This code hooks up two-way linking between a couple of textboxes on the page and the person object. The first line in the .ready() handler provides mapping of object to form field with the same field names as properties on the object. Note that .link() does NOT bind items into the textboxes when you call .link() – changes are mapped only when values change and you move out of the field. Strike one. The two following commands allow manual binding of values to specific DOM elements which is effectively a one-way bind. You specify the object and a then an explicit mapping where name is an ID in the document. The converter is required to explicitly assign the value to the element. Strike two. You can also detect changes to the underlying object and cause updates to the input elements bound. Unfortunately the syntax to do this is not very natural as you have to rely on the jQuery data object. To update an object’s properties and get change notification looks like this: function updateFirstName() { $(person).data("firstName", person.firstName + " (code updated)"); } This works fine in causing any linked fields to be updated. In the bindings above both the firstName input field and objFirst DOM element gets updated. But the syntax requires you to use a jQuery .data() call for each property change to ensure that the changes are tracked properly. Really? Sure you’re binding through multiple layers of abstraction now but how is that better than just manually assigning values? The code savings (if any) are going to be minimal. As much as I would like to have a WPF/Silverlight/Observable-like binding mechanism in client script, this plug-in doesn’t help much towards that goal in its current incarnation. While you can bind values, the ‘binder’ is too limited to be really useful. If initial values can’t be assigned from the mappings you’re going to end up duplicating work loading the data using some other mechanism. There’s no easy way to re-bind data with a different object altogether since updates trigger only through the .data members. Finally, any non-input elements have to be bound via code that’s fairly verbose and frankly may be more voluminous than what you might write by hand for manual binding and unbinding. Two way binding can be very useful but it has to be easy and most importantly natural. If it’s more work to hook up a binding than writing a couple of lines to do binding/unbinding this sort of thing helps very little in most scenarios. In talking to some of the developers the feature set for Data Link is not complete and they are still soliciting input for features and functionality. If you have ideas on how you want this feature to be more useful get involved and post your recommendations. As it stands, it looks to me like this component needs a lot of love to become useful. For this component to really provide value, bindings need to be able to be refreshed easily and work at the object level, not just the property level. It seems to me we would be much better served by a model binder object that can perform these binding/unbinding tasks in bulk rather than a tool where each link has to be mapped first. I also find the choice of creating a jQuery plug-in questionable – it seems a standalone object – albeit one that relies on the jQuery library – would provide a more intuitive interface than the current forcing of options onto a plug-in style interface. Out of the three Microsoft created components this is by far the least useful and least polished implementation at this point. jQuery Globalization http://github.com/jquery/jquery-global Globalization in JavaScript applications often gets short shrift and part of the reason for this is that natively in JavaScript there’s little support for formatting and parsing of numbers and dates. There are a number of JavaScript libraries out there that provide some support for globalization, but most are limited to a particular portion of globalization. As .NET developers we’re fairly spoiled by the richness of APIs provided in the framework and when dealing with client development one really notices the lack of these features. While you may not necessarily need to localize your application the globalization plug-in also helps with some basic tasks for non-localized applications: Dealing with formatting and parsing of dates and time values. Dates in particular are problematic in JavaScript as there are no formatters whatsoever except the .toString() method which outputs a verbose and next to useless long string. With the globalization plug-in you get a good chunk of the formatting and parsing functionality that the .NET framework provides on the server. You can write code like the following for example to format numbers and dates: var date = new Date(); var output = $.format(date, "MMM. dd, yy") + "\r\n" + $.format(date, "d") + "\r\n" + // 10/25/2010 $.format(1222.32213, "N2") + "\r\n" + $.format(1222.33, "c") + "\r\n"; alert(output); This becomes even more useful if you combine it with templates which can also include any JavaScript expressions. Assuming the globalization plug-in is loaded you can create template expressions that use the $.format function. Here’s the template I used earlier for the stock quote again with a couple of formats applied: <script id="stockTemplate" type="text/x-jquery-tmpl"> <div id="divStockQuote" class="errordisplay" style="width: 500px;"> <div class="label">Company:</div><div><b>${Company}(${Symbol})</b></div> <div class="label">Last Price:</div> <div>${$.format(LastPrice,"N2")}</div> <div class="label">Net Change:</div><div> {{if NetChange > 0}} <b style="color:green" >${NetChange}</b> {{else}} <b style="color:red" >${NetChange}</b> {{/if}} </div> <div class="label">Last Update:</div> <div>${$.format(LastQuoteTime,"MMM dd, yyyy")}</div> </div> </script> There are also parsing methods that can parse dates and numbers from strings into numbers easily: alert($.parseDate("25.10.2010")); alert($.parseInt("12.222")); // de-DE uses . for thousands separators As you can see culture specific options are taken into account when parsing. The globalization plugin provides rich support for a variety of locales: Get a list of all available cultures Query cultures for culture items (like currency symbol, separators etc.) Localized string names for all calendar related items (days of week, months) Generated off of .NET’s supported locales In short you get much of the same functionality that you already might be using in .NET on the server side. The plugin includes a huge number of locales and an Globalization.all.min.js file that contains the text defaults for each of these locales as well as small locale specific script files that define each of the locale specific settings. It’s highly recommended that you NOT use the huge globalization file that includes all locales, but rather add script references to only those languages you explicitly care about. Overall this plug-in is a welcome helper. Even if you use it with a single locale (like en-US) and do no other localization, you’ll gain solid support for number and date formatting which is a vital feature of many applications. Changes for Microsoft It’s good to see Microsoft coming out of its shell and away from the ‘not-built-here’ mentality that has been so pervasive in the past. It’s especially good to see it applied to jQuery – a technology that has stood in drastic contrast to Microsoft’s own internal efforts in terms of design, usage model and… popularity. It’s great to see that Microsoft is paying attention to what customers prefer to use and supporting the customer sentiment – even if it meant drastically changing course of policy and moving into a more open and sharing environment in the process. The additional jQuery support that has been introduced in the last two years certainly has made lives easier for many developers on the ASP.NET platform. It’s also nice to see Microsoft submitting proposals through the standard jQuery process of plug-ins and getting accepted for various very useful projects. Certainly the jQuery Templates plug-in is going to be very useful to many especially since it will be baked into the jQuery core in jQuery 1.5. I hope we see more of this type of involvement from Microsoft in the future. Kudos!© Rick Strahl, West Wind Technologies, 2005-2010Posted in jQuery  ASP.NET  

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  • VS 2010 JavaScript editor – matching braces highlighting – is it so difficult to implement?

    - by AGS777
    I do not know. Just curious. But first things first. As a web developer I spend about 80% of my work-time editing JavaScript code. And since my server-side platform is .NET then it would be very convenient to have decent JavaScript text editor within Visual Studio IDE. So, Visual Studio 2010 is out. Downloaded and installed. What were my expectations regarding JavaScript editor? Pretty low, actually.  I just wanted to have matching braces highlighted eventually. That’s all. Yes, I know about Ctrl + ] shortcut but it is not event remotely close to convenience. And the result? Alas. Without further ado, just look at some real-world fragment of code from jQuery Templates Proposal experimental plugin as I see it in Notepad++, Notepad2 and Visual Studio 2010 editors respectively: Notepad++ Notepad2 Visual Studio 2010 Look at the highlighted parentheses, regular expression literals, numbers. Do you have a feeling that the last screenshot is not very informative in comparison with the other ones? If yes, then my question is why? Instead I was given an IntelliSense. Sorry, but I do not need it to rot my mind. Especially the one which does not always work properly (try to use it with base2 library for example). With all the expressive power of the language I have to know what I am doing. Instead I still have the same plain old Notepad with some of the JavaScript keywords colorized, plus partially functional/useful IntelliSense. What I do need, is just a little help to make less errors when I type the code – some essential text editor facilities that I really need. Give me that and only then feel free to improve on something else. Maybe I am wrong. Then, sorry. Just cannot believe that I have to wait for another couple of years to get very basic code editor feature.  

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  • JavaScript Data Binding Frameworks

    - by dwahlin
    Data binding is where it’s at now days when it comes to building client-centric Web applications. Developers experienced with desktop frameworks like WPF or web frameworks like ASP.NET, Silverlight, or others are used to being able to take model objects containing data and bind them to UI controls quickly and easily. When moving to client-side Web development the data binding story hasn’t been great since neither HTML nor JavaScript natively support data binding. This means that you have to write code to place data in a control and write code to extract it. Although it’s certainly feasible to do it from scratch (many of us have done it this way for years), it’s definitely tedious and not exactly the best solution when it comes to maintenance and re-use. Over the last few years several different script libraries have been released to simply the process of binding data to HTML controls. In fact, the subject of data binding is becoming so popular that it seems like a new script library is being released nearly every week. Many of the libraries provide MVC/MVVM pattern support in client-side JavaScript apps and some even integrate directly with server frameworks like Node.js. Here’s a quick list of a few of the available libraries that support data binding (if you like any others please add a comment and I’ll try to keep the list updated): AngularJS MVC framework for data binding (although closely follows the MVVM pattern). Backbone.js MVC framework with support for models, key/value binding, custom events, and more. Derby Provides a real-time environment that runs in the browser an in Node.js. The library supports data binding and templates. Ember Provides support for templates that automatically update as data changes. JsViews Data binding framework that provides “interactive data-driven views built on top of JsRender templates”. jQXB Expression Binder Lightweight jQuery plugin that supports bi-directional data binding support. KnockoutJS MVVM framework with robust support for data binding. For an excellent look at using KnockoutJS check out John Papa’s course on Pluralsight. Meteor End to end framework that uses Node.js on the server and provides support for data binding on  the client. Simpli5 JavaScript framework that provides support for two-way data binding. WinRT with HTML5/JavaScript If you’re building Windows 8 applications using HTML5 and JavaScript there’s built-in support for data binding in the WinJS library.   I won’t have time to write about each of these frameworks, but in the next post I’m going to talk about my (current) favorite when it comes to client-side JavaScript data binding libraries which is AngularJS. AngularJS provides an extremely clean way – in my opinion - to extend HTML syntax to support data binding while keeping model objects (the objects that hold the data) free from custom framework method calls or other weirdness. While I’m writing up the next post, feel free to visit the AngularJS developer guide if you’d like additional details about the API and want to get started using it.

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  • This Week in Geek History: Gmail Goes Public, Deep Blue Wins at Chess, and the Birth of Thomas Edison

    - by Jason Fitzpatrick
    Every week we bring you a snapshot of the week in Geek History. This week we’re taking a peek at the public release of Gmail, the first time a computer won against a chess champion, and the birth of prolific inventor Thomas Edison. Gmail Goes Public It’s hard to believe that Gmail has only been around for seven years and that for the first three years of its life it was invite only. In 2007 Gmail dropped the invite only requirement (although they would hold onto the “beta” tag for another two years) and opened its doors for anyone to grab a username @gmail. For what seemed like an entire epoch in internet history Gmail had the slickest web-based email around with constant innovations and features rolling out from Gmail Labs. Only in the last year or so have major overhauls at competitors like Hotmail and Yahoo! Mail brought other services up to speed. Can’t stand reading a Week in Geek History entry without a random fact? Here you go: gmail.com was originally owned by the Garfield franchise and ran a service that delivered Garfield comics to your email inbox. No, we’re not kidding. Deep Blue Proves Itself a Chess Master Deep Blue was a super computer constructed by IBM with the sole purpose of winning chess matches. In 2011 with the all seeing eye of Google and the amazing computational abilities of engines like Wolfram Alpha we simply take powerful computers immersed in our daily lives for granted. The 1996 match against reigning world chest champion Garry Kasparov where in Deep Blue held its own, but ultimately lost, in a  4-2 match shook a lot of people up. What did it mean if something that was considered such an elegant and quintessentially human endeavor such as chess was so easy for a machine? A series of upgrades helped Deep Blue outright win a match against Kasparov in 1997 (seen in the photo above). After the win Deep Blue was retired and disassembled. Parts of Deep Blue are housed in the National Museum of History and the Computer History Museum. Birth of Thomas Edison Thomas Alva Edison was one of the most prolific inventors in history and holds an astounding 1,093 US Patents. He is responsible for outright inventing or greatly refining major innovations in the history of world culture including the phonograph, the movie camera, the carbon microphone used in nearly every telephone well into the 1980s, batteries for electric cars (a notion we’d take over a century to take seriously), voting machines, and of course his enormous contribution to electric distribution systems. Despite the role of scientist and inventor being largely unglamorous, Thomas Edison and his tumultuous relationship with fellow inventor Nikola Tesla have been fodder for everything from books, to comics, to movies, and video games. Other Notable Moments from This Week in Geek History Although we only shine the spotlight on three interesting facts a week in our Geek History column, that doesn’t mean we don’t have space to highlight a few more in passing. This week in Geek History: 1971 – Apollo 14 returns to Earth after third Lunar mission. 1974 – Birth of Robot Chicken creator Seth Green. 1986 – Death of Dune creator Frank Herbert. Goodnight Dune. 1997 – Simpsons becomes longest running animated show on television. Have an interesting bit of geek trivia to share? Shoot us an email to [email protected] with “history” in the subject line and we’ll be sure to add it to our list of trivia. Latest Features How-To Geek ETC Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware How to Change the Default Application for Android Tasks Stop Believing TV’s Lies: The Real Truth About "Enhancing" Images The How-To Geek Valentine’s Day Gift Guide Inspire Geek Love with These Hilarious Geek Valentines RGB? CMYK? Alpha? What Are Image Channels and What Do They Mean? Clean Up Google Calendar’s Interface in Chrome and Iron The Rise and Fall of Kramerica? [Seinfeld Video] GNOME Shell 3 Live CDs for OpenSUSE and Fedora Available for Testing Picplz Offers Special FX, Sharing, and Backup of Your Smartphone Pics BUILD! An Epic LEGO Stop Motion Film [VIDEO] The Lingering Glow of Sunset over a Winter Landscape Wallpaper

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  • Silverlight Cream for March 22, 2010 -- #817

    - by Dave Campbell
    In this Issue: Bart Czernicki, Tim Greenfield, Andrea Boschin(-2-), AfricanGeek, Fredrik Normén, Ian Griffiths, Christian Schormann, Pete Brown, Jeff Handley, Brad Abrams, and Tim Heuer. Shoutout: At the beginning of MIX10, Brad Abrams reported Silverlight 4 and RIA Services Release Candidate Available NOW From SilverlightCream.com: Using the Bing Maps Silverlight control on the Windows Phone 7 Bart Czernicki has a very cool BingMaps and WP7 tutorial up... you're going to want to bookmark this one for sure! Code included and external links... thanks Bart! Silverlight Rx DataClient within MVVM Tim Greenfield has a great post up about Rx and MVVM with Silverlight 3. Lots of good insight into Rx and interesting code bits. SilverVNC - a VNC Viewer with Silverlight 4.0 RC Andrea Boschin digs into Silverlight 4 RC and it's full-trust on sockets and builds an implementation of RFB protocol... give it a try and give Andrea some feedback. Chromeless Window for OOB applications in Silverlight 4.0 RC Andrea Boschin also has a post up on investigating the OOB no-chrome features in SL4RC. Windows Phone 7 and WCF AfricanGeek has his latest video tutorial up and it's on WCF and WP7... I've got a feeling we're all going to have to get our arms around this. Some steps for moving WCF RIA Services Preveiw to the RC version Fredrik Normén details his steps in transitioning to the RC version of RIA Services. Silverlight Business Apps: Module 8.5 - The Value of MEF with Silverlight Ian Griffiths has a video tutorial up at Channel 9 on MEF and Silverlight, posted by John Papa Introducing Blend 4 – For Silverlight, WPF and Windows Phone Christian Schormann has an early MIX10 post up about te new features in Expression Blend with regard to Silverlight, WPF, and WP7. Building your first Silverlight for Windows Phone Application Pete Brown has his first post up on building a WP7 app with the MIX10 bits. Lookups in DataGrid and DataForm with RIA Services Jeff Handley elaborates on a post by someone else about using lookup data in the DataGrid and DataForm with RIA Services Silverlight 4 + RIA Services - Ready for Business: Starting a New Project with the Business Application Template Brad Abrams is starting a series highlighting the key features of Silverlight 4 and RIA with the new releases. He has a post up Silverlight 4 + RIA Services - Ready for Business: Index, including links and source. Then in this first post of the series, he introduces the Business Application Template. Custom Window Chrome and Events Watch a tutorial video by Tim Heuer on creating custom chrome for OOB apps. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • How to find and fix performance problems in ORM powered applications

    - by FransBouma
    Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

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  • Databases in Source Control

    - by Grant Fritchey
    I’ve been working as a database professional for quite a long time. But originally, I was a developer. And I loved being a developer. There was this constant feedback loop of a job well done, your code compiled and it ran. Every time this happened successfully, you’d check it into source control. These days you have to add another step; the code passed all the tests, unit, line, regression, qa, whatever, then into source control it goes. As a matter of fact, when I first made the jump from developer to DBA/database developer/database professional, source control was the one thing I couldn’t believe was missing from the DBA toolbox. Come to find out, source control was only the beginning of what was missing from your standard DBAs set of skills. Don’t get me wrong. I’m not disrespecting the DBA. They’re focused where they should be, on your production data. But there has to be a method for developing applications that include databases and the database side of that development and deployment process has long been lacking. This lack of development and deployment methodologies is a part of what has given rise to some of the wackier implementations of Object Relational Mapping tools, the NoSQL movement, and some of the other foul cursing that is directed towards databases, DBAs, and database development by application developers. Some of that is well earned. A lot isn’t. But it is a fact that database professionals, in general, do not have as sophisticated a model for managing development and deployment as application developers do. We could charge out and start trying to come up with our own standards and methods. I’m sure people have done exactly that. However, I’m lazy, and not terribly bright. Rather than try to invent a whole new process, I’m going to look to my developer roots and choose instead to emulate the developers. They’re sitting over there across the hall from me working with SCRUM/Agile/Waterfall/Object Driven/Feature Driven/Test Driven development processes that they’ve been polishing for years. What if I just started working on database development the same way they work on code development? Win! Ah, but now I have to have a mechanism for treating my database like application code. First, I need a method for getting it into source control. That’s where Red Gate’s SQL Source Control comes into the picture. SQL Source Control works within SQL Server Management Studio to connect your database objects up to the source control system of your choice. Right out of the box SQL Source Control can link to TFS, SVN or Vault. With a little work you can connect it to Git or just about any other source control system. With the ability to get my database into source control, a lot of possibilities for more direct integration with the application development teams open up.

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  • Silverlight Cream for March 10, 2010 -- #810

    - by Dave Campbell
    In this Issue: Andrea Boschin, Jeremy Likness(-2-), Andrew Veresov, Nokola, SilverLaw, Gill Cleeren, Jim Wightman and Jeremy Likness, Viktor Larsson(-2-), and Walter Ferrari. Shoutouts: Viktor Larsson has a post up about Silverlight Market Penetration ... hope to meet you at MIX10, Viktor! Gergely Orosz has posted the Slides and code for the presentation “An Introduction to Silverlight” It appears that if I miss a day, I can pretty much do an all-submittal post :) From SilverlightCream.com: Writing an AsyncLoader to enqueue long running operations Andrea Boschin has a tutorial on SilverlightShow where he's building up an asynch service to deal with a long-running app on the server. MVVM with MEF in Silverlight: Video Tutorial Jeremy Likness has a video tutorial up for helping beginners wire up MVVM and MEF to Silverlight. Source code for the app in the video is downloadable. MVVM with MEF in Silverlight Video Tutorial Part 2: Plugins and Metadata In part 2, Jeremy Likness redesigns the app using metadata to turn the shapes into objects, and then show how easy it is to add a new plugin... and the source for the app is downloadable. Binding a Converter Parameter Andrew Veresov has a nice code-filled solution up for those times that you need to bind a ConverterParameter value. EasyPainter: Lion Hair styling Nokola has not been idle with Easy Painter... now he's added "Lion Hair" to the list of stylings you can apply... guess if you want to change someone's 'mane' ... sorry! Twisting Navigation - Silverlight 3 SilverLaw has another control up - a "Twisting Navigation" control... very cool :) ... and since I'm behind the curve, he already has an update in the Expression Gallery as noted in his post, and a video tutorial on implementing it in an application... and if you understand German, turn up the sound :) Uploading and downloading images using a WCF service with Silverlight Gill Cleeren has a tutorial up at SilverlightShow on uploading and downloading images using WCF Services in Silverlight New Windows Phone 7 Community Developer Hub Jim Wightman and Jeremy Likness have a very cool Silverlight page up where you can paste the URL of your XAP in and have it display in a "Windows 7 Series Phone" ... and that's all I'm saying about that. XAML Transformation 101 Viktor Larsson is discussing Transforms in XAML and has a nice tutorial up that is easily the beginning of a carousel... you may also want to check out his other posts... I'm adding him to my list. Silverlight 4 Webcam Demo In this post, Viktor Larsson has a tutorial up for using the WebCam. This is from a beginner perspective, so if you haven't jumped in, now's a good time. How to extend Bing Maps Silverlight with an elevation profile graph - Part 1 Walter Ferrari has a post up at SilverlightShow discussing extensions to BingMaps such as creating routes using GeoCoding and Route Services plus drawing lines on the maps and getting coordinates of the points. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    MIX10

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  • OWB 11gR2 &ndash; OLAP and Simba

    - by David Allan
    Oracle Warehouse Builder was the first ETL product to provide a single integrated and complete environment for managing enterprise data warehouse solutions that also incorporate multi-dimensional schemas. The OWB 11gR2 release provides Oracle OLAP 11g deployment for multi-dimensional models (in addition to support for prior releases of OLAP). This means users can easily utilize Simba's MDX Provider for Oracle OLAP (see here for details and cost) which allows you to use the powerful and popular ad hoc query and analysis capabilities of Microsoft Excel PivotTables® and PivotCharts® with your Oracle OLAP business intelligence data. The extensions to the dimensional modeling capabilities have been built on established relational concepts, with the option to seamlessly move from a relational deployment model to a multi-dimensional model at the click of a button. This now means that ETL designers can logically model a complete data warehouse solution using one single tool and control the physical implementation of a logical model at deployment time. As a result data warehouse projects that need to provide a multi-dimensional model as part of the overall solution can be designed and implemented faster and more efficiently. Wizards for dimensions and cubes let you quickly build dimensional models and realize either relationally or as an Oracle database OLAP implementation, both 10g and 11g formats are supported based on a configuration option. The wizard provides a good first cut definition and the objects can be further refined in the editor. Both wizards let you choose the implementation, to deploy to OLAP in the database select MOLAP: multidimensional storage. You will then be asked what levels and attributes are to be defined, by default the wizard creates a level bases hierarchy, parent child hierarchies can be defined in the editor. Once the dimension or cube has been designed there are special mapping operators that make it easy to load data into the objects, below we load a constant value for the total level and the other levels from a source table.   Again when the cube is defined using the wizard we can edit the cube and define a number of analytic calculations by using the 'generate calculated measures' option on the measures panel. This lets you very easily add a lot of rich analytic measures to your cube. For example one of the measures is the percentage difference from a year ago which we can see in detail below. You can also add your own custom calculations to leverage the capabilities of the Oracle OLAP option, either by selecting existing template types such as moving averages to defining true custom expressions. The 11g OLAP option now supports percentage based summarization (the amount of data to precompute and store), this is available from the option 'cost based aggregation' in the cube's configuration. Ensure all measure-dimensions level based aggregation is switched off (on the cube-dimension panel) - previously level based aggregation was the only option. The 11g generated code now uses the new unified API as you see below, to generate the code, OWB needs a valid connection to a real schema, this was not needed before 11gR2 and is a new requirement since the OLAP API which OWB uses is not an offline one. Once all of the objects are deployed and the maps executed then we get to the fun stuff! How can we analyze the data? One option which is powerful and at many users' fingertips is using Microsoft Excel PivotTables® and PivotCharts®, which can be used with your Oracle OLAP business intelligence data by utilizing Simba's MDX Provider for Oracle OLAP (see Simba site for details of cost). I'll leave the exotic reporting illustrations to the experts (see Bud's demonstration here), but with Simba's MDX Provider for Oracle OLAP its very simple to easily access the analytics stored in the database (all built and loaded via the OWB 11gR2 release) and get the regular features of Excel at your fingertips such as using the conditional formatting features for example. That's a very quick run through of the OWB 11gR2 with respect to Oracle 11g OLAP integration and the reporting using Simba's MDX Provider for Oracle OLAP. Not a deep-dive in any way but a quick overview to illustrate the design capabilities and integrations possible.

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  • Silverlight User Group of Switzerland (SLUGS)

    - by Laurent Bugnion
    Last Thursday, the Silverlight Firestarter event took place in Redmond, and was streamed live to a large audience worldwide (around 20’000 people). Approximately 30 if them were in Wallisellen near Zurich, in Microsoft Switzerland’s offices. This was not only a great occasion to learn more about the future of Silverlight and to see great demos, but also it was the very first meeting of the Silverlight User Group of Switzerland (SLUGS). Having 30 people for a first meeting was a great success, especially if we consider that it was REALLY cold that night, that it had snowed 20 cm the night before! We all had a good time, and 3 lucky winners went back home with a prize: One LG Optimus 7 Windows Phone and two copies of Silverlight 4 Unleashed. Congratulations to the winners! After the keynote (which went in a whirlwind, shortest 90 minutes ever!), we all had pizza and beverages generously sponsored by the Swiss DPE team, of which not less than 5 guys came to the event! Thanks to Stefano, Ronnie, Sascha, Big Mike and Ken for attending! We decided to have meetings every month. Stay tuned for announcements on when and where the events will take place. We are also in the process of creating various groups online where the attendees can find more information. For instance, I created a group on Flickr where the pictures taken at events will be published. The group is public, and the pictures of the first event are already online! We also have the already known page at http://www.slugs.ch/, check it out. A national group Even though the first event was in Zurich, and that 3 of the founding members live nearby, we would like to try and be a national group. That means having events sometimes in other parts of Switzerland, collaborating with other local user groups, etc. Stay tuned for more Join! We want you, we need you If you are doing Silverlight, for a living or as a hobby, if you are interested in user experience, XAML, Expression Blend and many more topics, you should consider joining! This is a great occasion to exchange experiences, to learn from Silverlight experts, to hear sessions about various topics related to Silverlight, etc. If you want to talk about a topic that is of interest to you, If you want to propose a topic of discussion Or if you just want to hang out then go to http://www.slugs.ch and register! Cheers, Laurent   Laurent Bugnion (GalaSoft) Subscribe | Twitter | Facebook | Flickr | LinkedIn

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