Search Results

Search found 19967 results on 799 pages for 'document template'.

Page 307/799 | < Previous Page | 303 304 305 306 307 308 309 310 311 312 313 314  | Next Page >

• xsl:for-each not supported in this context

  - by alexbf

  Hi! I have this XSLT document : <xsl:stylesheet version="1.0" xmlns:mstns="http://www.w3.org/2001/XMLSchema" xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/> <xsl:template match="/MyDocRootElement"> <xs:schema id="DataSet" targetNamespace="http://www.w3.org/2001/XMLSchema" attributeFormDefault="qualified" elementFormDefault="qualified" > <xs:element name="DataSet" msdata:IsDataSet="true"> <xs:complexType> <xs:choice maxOccurs="unbounded"> <xs:element name="Somename"> </xs:element> <xs:element name="OtherName"> </xs:element> <!-- FOR EACH NOT SUPPORTED? --> <xsl:for-each select="OtherElements/SubElement"> <xs:element name="OtherName"> </xs:element> </xsl:for-each> </xs:choice> </xs:complexType> </xs:element> </xs:schema> </xsl:template> </xsl:stylesheet> I have a validation error saying that the "for-each element is not supported in this context" I am guessing it has something to do with the xs namespace validation. Any ideas on how can I make this work? (Exclude validation?) Thanks Alex

  Read the article

• Constructor initializer list: code from the C++ Primer, chapter 16

  - by Alexandros Gezerlis

  Toward the end of Chapter 16 of the "C++ Primer" I encountered the following code (I've removed a bunch of lines): class Sales_item { public: // default constructor: unbound handle Sales_item(): h() { } private: Handle<Item_base> h; // use-counted handle }; My problem is with the Sales_item(): h() { } line. For the sake of completeness, let me also quote the parts of the Handle class template that I think are relevant to my question (I think I don't need to show the Item_base class): template <class T> class Handle { public: // unbound handle Handle(T *p = 0): ptr(p), use(new size_t(1)) { } private: T* ptr; // shared object size_t *use; // count of how many Handles point to *ptr }; I would have expected something like either: a) Sales_item(): h(0) { } which is a convention the authors have used repeatedly in earlier chapters, or b) Handle<Item_base>() if the intention was to invoke the default constructor of the Handle class. Instead, what the book has is Sales_item(): h() { }. My gut reaction is that this is a typo, since h() looks suspiciously similar to a function declaration. On the other hand, I just tried compiling under g++ and running the example code that uses this class and it seems to be working correctly. Any thoughts?

  Read the article

• XUL: Printing value from SQL query without using value attribute

  - by Grip

  I want to print the results of an SQL query in XUL with word-wrapping using the description tag. I have the following code: <grid> <columns> <column flex="2" /> <column flex="1" /> </columns> <rows datasources="chrome://glossary/content/db/development.sqlite3" ref="?" querytype="storage" > <template> <query>select distinct * from Terms</query> <action> <row uri="?"> <description value="?name" /> <description value="?desc" /> </row> </action> </template> </rows> This works for printing the data, but since I'm using the value attribute of description, there's no word-wrapping. I don't understand entirely what I'm doing with the value attribute, but I don't seem to be able to get the values of my SQL query in any other way. So, how could I get those values without the value tag? Thanks.

  Read the article

• XSLT special characters

  - by Apurv

  In the following XSL transformation how do I output the '<' and '' symbol? Input XML: <TestResult bugnumber="3214" testname="display.methods::close->test_ManyInvoke" errortype="Failure"><ErrorMessage><![CDATA[calling close() method failed - expected:<2>]]></ErrorMessage> XSLT: <xsl:template match="TestResult"> <xsl:variable name="errorMessage"> <xsl:value-of select="ErrorMessage" disable-output-escaping="yes"/> </xsl:variable> <Test name='{@testname}'> <TestResult> <Passed>false</Passed> <State>failure</State> <Metadata> <Entry name='bugnumber' value='{@bugnumber}' /> </Metadata> <TestOutput> <Metadata> <Entry name='ErrorMessage' value='{$errorMessage}' /> </Metadata> </TestOutput> </TestResult> </Test> </xsl:template> Output XML: <Test name="display.methods::close-&gttest_ManyInvoke"> <TestResult> <Passed>false</Passed> <State>failure</State> <Metadata> <Entry name="bugnumber" value="3214"/> </Metadata> <TestOutput> <Metadata> <Entry name="ErrorMessage" value="calling close() method failed - expected:&lt;2&gt;"/> </Metadata> </TestOutput> </TestResult> </Test>

  Read the article

• How do I overload () operator with two parameters; like (3,5)?

  - by hkBattousai

  I have a mathematical matrix class. It contains a member function which is used to access any element of the class. template >class T> class Matrix { public: // ... void SetElement(T dbElement, uint64_t unRow, uint64_t unCol); // ... }; template <class T> void Matrix<T>::SetElement(T Element, uint64_t unRow, uint64_t unCol) { try { // "TheMatrix" is define as "std::vector<T> TheMatrix" TheMatrix.at(m_unColSize * unRow + unCol) = Element; } catch(std::out_of_range & e) { // Do error handling here } } I'm using this method in my code like this: // create a matrix with 2 rows and 3 columns whose elements are double Matrix<double> matrix(2, 3); // change the value of the element at 1st row and 2nd column to 6.78 matrix.SetElement(6.78, 1, 2); This works well, but I want to use operator overloading to simplify things, like below: Matrix<double> matrix(2, 3); matrix(1, 2) = 6.78; // HOW DO I DO THIS?

  Read the article

• Django Model Formset Pre-Filled Value Problem

  - by user552377

  Hi, i'm trying to use model formsets with Django. When i load forms template, i see that it's filled-up with previous values. Is there a caching mechanism that i should stop, or what? Thanks for your help, here is my code: models.py class FooModel( models.Model ): a_field = models.FloatField() b_field = models.FloatField() def __unicode__( self ): return self.a_field forms.py from django.forms.models import modelformset_factory FooFormSet = modelformset_factory(FooModel) views.py def foo_func(request): if request.method == 'POST': formset = FooFormSet(request.POST, request.FILES, prefix='foo_prefix' ) if formset.is_valid(): formset.save() return HttpResponseRedirect( '/true/' ) else: return HttpResponseRedirect( '/false/' ) else: formset = FooFormSet(prefix='foo_prefix') variables = RequestContext( request , { 'formset':formset , } ) return render_to_response('footemplate.html' , variables ) template: <form method="post" action="."> {% csrf_token %} <input type="submit" value="Submit" /> <table id="FormsetTable" border="0" cellpadding="0" cellspacing="0"> <tbody> {% for form in formset.forms %} <tr> <td>{{ form.a_field }}</td> <td>{{ form.b_field }}</td> </tr> {% endfor %} </tbody> </table> {{ formset.management_form }} </form>

  Read the article

• Trying to grab several random videos from database, but it just shows the same one all the time.

  - by Birk

  Hi guys, I'm trying to grab several random videos from my database, and have them show on a page. However, it just keeps on grabbing the same video rather than several different ones. So I end up with 5 of the same video rather than 5 different ones. Here's the grab random PHP code file... and after it is the template output file. //===================================================== // Random | Previous | Next //===================================================== $show['random'] = $db->quick_fetch( "SELECT file_id, title, title_seo, category_id, thumb FROM files WHERE files.category_id = '".$show['main']['category_id']."' AND files.verified=1 ORDER BY RAND() LIMIT 0,1; "); Here's the template CSS html thingy code I have this pasted 5 times to show 5 random videos <td valign="top" width="53%"><? $sql="select * from files ORDER BY rand() limit 0,5"; $res=@mysql_query($sql); $data=@mysql_result($res,0,'filename'); $id=@mysql_result($res,0,'file_id'); $title=@mysql_result($res,0,'title'); $title2=str_replace(" ", "-",$title); $path="{$siteurl}/media/{$file.random.file_id}/{$file.random.title_seo}/"; $img="{$siteurl}/thumbs/{$file.random.thumb}"; echo " {$file.random.title}"

  Read the article

• Preallocating memory with C++ in realtime environment

  - by Elazar Leibovich

  I'm having a function which gets an input buffer of n bytes, and needs an auxillary buffer of n bytes in order to process the given input buffer. (I know vector is allocating memory at runtime, let's say that I'm using a vector which uses static preallocated memory. Imagine this is NOT an STL vector.) The usual approach is void processData(vector<T> &vec) { vector<T> &aux = new vector<T>(vec.size()); //dynamically allocate memory // process data } //usage: processData(v) Since I'm working in a real time environment, I wish to preallocate all the memory I'll ever need in advance. The buffer is allocated only once at startup. I want that whenever I'm allocating a vector, I'll automatically allocate auxillary buffer for my processData function. I can do something similar with a template function static void _processData(vector<T> &vec,vector<T> &aux) { // process data } template<size_t sz> void processData(vector<T> &vec) { static aux_buffer[sz]; vector aux(vec.size(),aux_buffer); // use aux_buffer for the vector _processData(vec,aux); } // usage: processData<V_MAX_SIZE>(v); However working alot with templates is not much fun (now let's recompile everything since I changed a comment!), and it forces me to do some bookkeeping whenever I use this function. Are there any nicer designs around this problem?

  Read the article

• getting OSGI Bundle from Eclipse IConfigurationElement

  - by Hayden Marchant

  Hi there, I am looking for extensions that implement a specific extension point, and am using the following acceptable method to do this: IExtensionRegistry extensionRegistry = Platform.getExtensionRegistry(); if (extensionRegistry == null) { return TEMPLATES; } IConfigurationElement[] config = extensionRegistry.getConfigurationElementsFor("com.ibm.im.launchpoint.templates.template"); I then would like to get the version of the defining bundle. I would use the following API, but the API for PluginVersionIdentifier is deprecated: for (IConfigurationElement e : config) { BlueprintTemplate template = new BlueprintTemplate(); IExtension declaringExtension = e.getDeclaringExtension(); PluginVersionIdentifier versionIdentifier = declaringExtension.getDeclaringPluginDescriptor().getVersionIdentifier(); I could not find an alternative in the new API - i.e. from a IConfigurationElement, how do I get the version id descriptor of the bundle. Obviously, from the Bundle I can get the version using the Bundle.getHeaders(), getting the Bundle-Version value - but how do I get the Bundle in the first place??? Platform.getBundle(bundleId) is not enough since I might have multiple versions of same bundle installed, and I need to know who I am. At the moment I have a chicken & egg situation, and the only solution I have is the above deprecated API.

  Read the article

• Wpf ItemsControl with datatemplate, problem with doubled border for some items

  - by ksirg

  Hi, I have simple ItemsControl with custom datatemplate, template contains only textblock with border. All items should be displayed vericaly one after another, but some items have extra border. How can I remove it? I want to achieve something similar to enso launcher, it looks like My implementation looks like this here is my xaml code: <Window x:Class="winmole.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" x:Name="hostWindow" Height="Auto" MinHeight="100" MinWidth="100" Width="Auto" Padding="10" AllowsTransparency="True" WindowStyle="None" Background="Transparent" Top="0" Left="0" SizeToContent="WidthAndHeight" Topmost="True" Loaded="Window_Loaded" KeyUp="Window_KeyUp" > <Window.Resources> <!--Simple data template for Items--> <DataTemplate x:Key="itemsTemplate"> <Border Background="Black" Opacity="0.9" HorizontalAlignment="Left" CornerRadius="0,2,2,0"> <TextBlock Text="{Binding Path=Title}" TextWrapping="Wrap" FontFamily="Georgia" FontSize="30" Height="Auto" HorizontalAlignment="Left" VerticalAlignment="Stretch" TextAlignment="Left" Padding="5" Margin="0" Foreground="Yellow"/> </Border> </DataTemplate> </Window.Resources> <DockPanel> <ItemsControl DockPanel.Dock="Bottom" Name="itcPrompt" ItemsSource="{Binding ElementName=hostWindow, Path=DataItems}" ItemTemplate="{StaticResource itemsTemplate}" > <ItemsControl.ItemsPanel> <ItemsPanelTemplate> <WrapPanel Orientation="Vertical" /> </ItemsPanelTemplate> </ItemsControl.ItemsPanel> </ItemsControl> </DockPanel>

  Read the article

• If statement doesn't work? do download without filed name and email

  - by user1833871

  I've created some if / else statements to get a download when a user hit click jf he fields name and email but doesn"t work for my site http://my-easy-woodworking-projects.com because it is do download without field name and email contact.php is <?php $field_name = $_POST['cf_name']; $field_email = $_POST['cf_email']; $field_message = $_POST['cf_message']; $mail_to = '[email protected]'; $subject = 'Message from a site visitor '.$field_name; $body_message = 'From: '.$field_name."\n"; $body_message .= 'E-mail: '.$field_email."\n"; $body_message .= 'Message: '.$field_message; $headers = 'From: '.$field_email."\r\n"; $headers .= 'Reply-To: '.$field_email."\r\n"; $mail_status = mail($mail_to, $subject, $body_message, $headers); if ($mail_status) { echo <script>\n" echo "var str = \"download\"; \n"" echo "document.write(str.link("http://www.myshedplans.com/12BY8SHED.pdf"));\n" echo "</script>\n" } echo else { echo <script language="javascript" type="text/javascript"> echo // Print a message echo alert('Message failed. Please, send an email to [email protected]'); echo // Redirect to some page of the site. You can also specify full URL, e.g. http://template-help.com window.location = 'contact_page.html'; echo </script> }?>

  Read the article

• Typedef equivalence in function arguments

  - by Warren Seine

  Hi guys, The question is kind of hard to ask without an example so here it is: #include <vector> struct O { }; struct C { template <typename T> void function1(void (C::*callback)(const O*)); template <typename T> void function2(void (C::*callback)(const typename T::value_type)); void print(const O*); }; int main() { C c; c.function1< std::vector<O*> >(&C::print); // Success. c.function2< std::vector<O*> >(&C::print); // Fail. } The error that I am given is: error: no matching function for call to ‘C::function2(void (C::*)(const O*))’. Basically, the only difference between calls is that in function2, I'm more generic since I use the typedef std::vector<O*>::value_type which should resolve to O*, hence similar to function1. I'm using G++ 4.2.1 (I know it's old), but Comeau confirms I'm wrong. Why does the compilation fail?

  Read the article

• How can i split up a component using cfinclude and still use inheritance?

  - by rip747

  Note: this is just a simplized example of what i'm trying to do to get the idea across. The problem I'm having is that I want to use cfinclude inside cfcomponent so that i can group like methods into separate files for more manageability. The problem I'm running into is when i try to extend another component that also uses cfinclude to manage it's method as demostrated below. Note that ComponentA extends ComponentB: ComponentA ========== <cfcomponent output="false" extends="componentb"> <cfinclude template="componenta/methods.cfm"> </cfcomponent> componenta/methods.cfm ====================== <cffunction name="a"><cfreturn "componenta-a"></cffunction> <cffunction name="b"><cfreturn "componenta-b"></cffunction> <cffunction name="c"><cfreturn "componenta-c"></cffunction> <cffunction name="d"><cfreturn super.a()></cffunction> ComponentB ========== <cfcomponent output="false"> <cfinclude template="componentb/methods.cfm"> </cfcomponent> componentb/methods.cfm ====================== <cffunction name="a"><cfreturn "componentb-a"></cffunction> <cffunction name="b"><cfreturn "componentb-b"></cffunction> <cffunction name="c"><cfreturn "componentb-c"></cffunction> The issue is that when i try to initialize ComponentA I get an the error: "Routines cannot be declared more than once. The routine a has been declared twice in different templates." The whole reason for this is because when you use cfinclude it's evaluated at RUN TIME instead of COMPILE TIME. Short of moving the methods into the components themselves and eliminating the use of cfinclude, how can i get around this or does someone have a better idea splitting up large components?

  Read the article

• what is the best practice approach for n-tier application development with entity framework?

  - by samsur

  I am building an application using entity framework. I am using the T4 template to generate self tracking entities. Currently, I am thinking of creating the entity framework code in a separate project. In this same project, I would have partial classes with additional methods for the entities. I am thinking of creating a separate project for a service layer (WCF) with methods for the upper/presentation tier. The WCF layer will reference the entity framework project. The methods in the WCF layer will return the entities or accept the entities as the parameters. I am thinkg of creating a third project for the presentation layer (ASP.net), this will make calls to the WCF service but will also need to reference the entities as the WCF methods take these types as the parameters/return types. In short, i want to use the STE entities generated by the T4 template as a DTO to be used in all layers. I was originally thinking of creating a business logic layer that maps to each entities. Example: If i have a customer class, the Business Layer would have a CustomerBLL class and then methods in the customerBLL will be used by the service layer. I was also trying to create a DTO in this business layer. I however found that this approach is very time consuming and i do not see a major benefit as it would create more maintenance work. What is the best practice for n-tier application development using entity framework 4?

  Read the article

• Node.js/Express Partials problem: Can't be nested too deep?

  - by heorling

  I'm learning Node.js, Express, haml.js and liking it. I've run into a prety annoying problem though. I'm pretty new to this but have been getting nice results so far. I'm writing a jquery heavy web app that relies on a table containing divs. The divs slide around, switch back and fourth and are resized etc to my hearts content. What I'm looking for a way to switch (template?) the divs. Since I've been building in express and mimicking the chat example it would make sense to use partials. The rub is that I've been using inexplicit divs in haml, held within a td. The divs are cunstructed as follows: %tr %td .class1.class2.class3.classetc Which has worked fine cross browser. Parsing the classes works great for the js code to pass arguments around, fetch values etc. What I'd like to be able to do is something like: %tr %td .class1.class2.class3.classetc %ul#messages != this.partial('message.html.haml', { collection: messages }) Any combination I've tried with this has failed however. And I might have tried them all. If I could put a partial into that div I'd probably be set. And you can nest them as long as you use #ids instead of .classes. But if you use more than one class it breaks! I think that's the most accurate way of summing it up. How do you do this? I've checked out various templating solutions like mu.js and micro template like by John Resig. I earlier checked out this thread on templating engines. It's very possible I'm making some fundamental mistake here, I'm new to this. What's a good way to do this?

  Read the article

• C++, array declaration, templates, linker error

  - by justik

  There is a linker error in my SW. I am using the following structure based on h, hpp, cpp files. Some classes are templatized, some not, some have function templates. Declaration: test.h #ifndef TEST_H #define TEST_H class Test { public: template <typename T> void foo1(); void foo2 () }; #include "test.hpp" #endif Definition: test.hpp #ifndef TEST_HPP #define TEST_HPP template <typename T> void Test::foo1() {} inline void Test::foo2() {} //or in cpp file #endif CPP file: test.cpp #include "test.h" void Test::foo2() {} //or in hpp file as inline I have the following problem. The variable vars[] is declared in my h file test.h #ifndef TEST_H #define TEST_H char *vars[] = { "first", "second"...}; class Test { public: void foo(); }; #include "test.hpp" #endif and used as a local variable inside foo() method defined in hpp file as inline. test.hpp #ifndef TEST_HPP #define TEST_HPP inline void Test::foo() { char *var = vars[0]; //A Linker Error } #endif However, the following linker error occurs: Error 745 error LNK2005: "char * * vars" (?vars@@3PAPADA) already defined in test2.obj How and where to declare vars[] to avoid linker errors? After including #include "test.hpp" it is late to declare it...

  Read the article

• std::stringstream GCC Abnormal Behavior

  - by FlorianZ

  I have a very interesting problem with compiling a short little program on a Mac (GCC 4.2). The function below would only stream chars or strings into the stringstream, but not anything else (int, double, float, etc.) In fact, the fail flag is set if I attempt to convert for example an int into a string. However, removing the preprocessor flag: _GLIBCXX_DEBUG=1, which is set by default in XCode for the debug mode, will yield the desired results / correct behavior. Here is the simple function I am talking about. value is template variable of type T. Tested for int, double, float (not working), char and strings (working). template < typename T > const std::string Attribute<T>::getValueAsString() const { std::ostringstream stringValue; stringValue << value; return stringValue.str(); } Any ideas what I am doing wrong, why this doesn't work, or what the preprocessor flag does to make this not work anymore? Thanks!

  Read the article

• C++ -- Why should we use operator -> to access member functions of a SmartPtr?

  - by q0987

  Hello all, The question is given in the last two lines of code. template<class T> // template class for smart class SmartPtr { // pointers-to-T objects public: SmartPtr(T* realPtr = 0); T* operator->() const; T& operator*() const; T* Detach( void ) { T* pData = pointee; pointee = NULL; return pData; } private: T *pointee; ... }; class TestClass {} SmartPtr<TestClass> sPtr(new TestClass); TestClass* ptrA = sPtr->Detach(); // why I always see people use this method to access member functions of a Smart pointer. We can use sPtr-> b/c we have defined operator->() in SmartPtr. TestClass* ptrB = sPtr.Detach(); // Question: Is this a valid C++ way? If not, why? Thank you

  Read the article

• Checking if a function has C-linkage at compile-time

  - by scjohnno

  Is there any way to check if a given function is declared with C-linkage (that is, with extern "C") at compile-time? I am developing a plugin system. Each plugin can supply factory functions to the plugin-loading code. However, this has to be done via name (and subsequent use of GetProcAddress or dlsym). This requires that the functions be declared with C-linkage so as to prevent name-mangling. It would be nice to be able to throw a compiler error if the referred-to function is declared with C++-linkage (as opposed to finding out at runtime when a function with that name does not exist). Here's a simplified example of what I mean: extern "C" void my_func() { } void my_other_func() { } // Replace this struct with one that actually works template<typename T> struct is_c_linkage { static const bool value = true; }; template<typename T> void assertCLinkage(T *func) { static_assert(is_c_linkage<T>::value, "Supplied function does not have C-linkage"); } int main() { assertCLinkage(my_func); // Should compile assertCLinkage(my_other_func); // Should NOT compile } Thanks.

  Read the article

• In need of a Smarter Environmental Package Configuration

  - by Jeremy Liberman

  I am trying to set up a package template in SSIS, following the Wrox Programmer to Programmer book, SQL Server 2008 Integration Services: Problem - Design - Solution. I'm really liking this book even though it is 2008 and we're using SQL Server 2005. I've got a working package template that uses an Indirect XML package configuration to identify what environment (local developer, dev, QA, production, etc) the package is being run in. That locates the SQL Server package configuration for the environment. That set-up is great and all except for the environment variable at the very front of it all. My team would prefer it if the package could use the same environment resource locator as all our other applications and tools use, so we don't two environment markers with essentially the same information in them. Normally we look up a registry key in HKey_Local_Machine but the Registry Package Configuration type only lets you look up the HKey_Current_User registries. My first thought was to write a new Package Configuration Type class that extends the Registry type; after all we'd had such luck writing our own custom log provider. SSIS is super extendable, right? So there doesn't seem to be a way to write your own Package Configuration Types. Is there still some way I can configure my SSIS SQL Server package configuration from a HKLM registry key connection string? If this is not possible, what other workarounds are available? My idea is to write a PowerShell script that will create/modify the Environment Variable that the package will use by fetching the connection string from the registry. This way there's still two markers, but at least then it's automatically maintained and automated. Is this kind of workaround necessary? Thank you for your time.

  Read the article

• code is not compiling

  - by user323422

  template< class Type ,int Size = 3> class cStack { Type *m_array; int m_Top; int m_Size; public:cStack(); friend std::ostream& operator <<(std::ostream &, const cStack<Type,Size> &); }; template< class Type ,int Size > std::ostream& operator << ( std::ostream &os, const cStack<Type,Size> &s) { for( int i=0; i<=s.GetTop();i++) { os << s.m_array[i]; } return os; } on compilin it showing following error error LNK2019: unresolved external symbol "class std::basic_ostream<char,struct std::char_traits<char> > & __cdecl operator<<(class std::basic_ostream<char,struct std::char_traits<char> > &,class cStack<int,3> const &)" (??6@YAAAV?$basic_ostream@DU?$char_traits@D@std@@@std@@AAV01@ABV?$cStack@H$02@@@Z) referenced in function _main

  Read the article

• How string accepting interface should look like?

  - by ybungalobill

  Hello, This is a follow up of this question. Suppose I write a C++ interface that accepts or returns a const string. I can use a const char* zero-terminated string: void f(const char* str); // (1) The other way would be to use an std::string: void f(const string& str); // (2) It's also possible to write an overload and accept both: void f(const char* str); // (3) void f(const string& str); Or even a template in conjunction with boost string algorithms: template<class Range> void f(const Range& str); // (4) My thoughts are: (1) is not C++ish and may be less efficient when subsequent operations may need to know the string length. (2) is bad because now f("long very long C string"); invokes a construction of std::string which involves a heap allocation. If f uses that string just to pass it to some low-level interface that expects a C-string (like fopen) then it is just a waste of resources. (3) causes code duplication. Although one f can call the other depending on what is the most efficient implementation. However we can't overload based on return type, like in case of std::exception::what() that returns a const char*. (4) doesn't work with separate compilation and may cause even larger code bloat. Choosing between (1) and (2) based on what's needed by the implementation is, well, leaking an implementation detail to the interface. The question is: what is the preffered way? Is there any single guideline I can follow? What's your experience?

  Read the article

• how to download data which upload to gae ,

  - by zjm1126

  this is my code : import os from google.appengine.ext import webapp from google.appengine.ext.webapp import template from google.appengine.ext.webapp.util import run_wsgi_app from google.appengine.ext import db #from login import htmlPrefix,get_current_user class MyModel(db.Model): blob = db.BlobProperty() class BaseRequestHandler(webapp.RequestHandler): def render_template(self, filename, template_args=None): if not template_args: template_args = {} path = os.path.join(os.path.dirname(__file__), 'templates', filename) self.response.out.write(template.render(path, template_args)) class upload(BaseRequestHandler): def get(self): self.render_template('index.html',) def post(self): file=self.request.get('file') obj = MyModel() obj.blob = db.Blob(file.encode('utf8')) obj.put() self.response.out.write('upload ok') class download(BaseRequestHandler): def get(self): #id=self.request.get('id') o = MyModel.all().get() #self.response.out.write(''.join('%s: %s <br/>' % (a, getattr(o, a)) for a in dir(o))) self.response.out.write(o) application = webapp.WSGIApplication( [ ('/?', upload), ('/download',download), ], debug=True ) def main(): run_wsgi_app(application) if __name__ == "__main__": main() my index.html is : <form action="/" method="post"> <input type="file" name="file" /> <input type="submit" /> </form> and it show : <__main__.MyModel object at 0x02506830> but ,i don't want to see this , i want to download it , how to change my code to run, thanks

  Read the article

• Is there a way to create subdatabases as a kind of subfolders in sql server?

  - by user193655

  I am creating an application where there is main DB and where other data is stored in secondary databases. The secondary databases follow a "plugin" approach. I use SQL Server. A simple installation of the application will just have the mainDB, while as an option one can activate more "plug-ins" and for every plug-in there will be a new database. Now why I made this choice is because I have to work with an exisiting legacy system and this is the smartest thing I could figure to implement the plugin system. MainDB and Plugins DB have exactly the same schema (basically Plugins DB have some "special content", some important data that one can use as a kind of template - think to a letter template for example - in the application). Plugin DBs are so used in readonly mode, they are "repository of content". The "smart" thing is that the main application can also be used by "plugin writers", they just write a DB inserting content, and by making a backup of the database they creaetd a potential plugin (this is why all DBs has the same schema). Those plugins DB are downloaded from internet as there is a content upgrade available, every time the full PlugIn DB is destroyed and a new one with the same name is creaetd. This is for simplicity and even because the size of this DBs is generally small. Now this works, anyway I would prefer to organize the DBs in a kind of Tree structure, so that I can force the PlugIn DBs to be "sub-DBs" of the main application DB. As a workaround I am thinking of using naming rules, like: ApplicationDB (for the main application DB) ApplicationDB_PlugIn_N (for the N-th plugin DB) When I search for plugin 1 I try to connect to ApplicationDB_PlugIn_1, if I don't find the DB i raise an error. This situation can happen for example if som DBA renamed ApplicationDB_Plugin_1. So since those Plugin DBs are really dependant on ApplicationDB only I was trying to "do the subfolder trick". Can anyone suggest a way to do this? Can you comment on this self-made plugin approach I decribed above?

  Read the article

• SFINAE and detecting if a C++ function object returns void.

  - by Tom Swirly

  I've read the various authorities on this, include Dewhurst and yet haven't managed to get anywhere with this seemingly simple question. What I want to do is to call a C++ function object, (basically, anything you can call, a pure function or a class with ()), and return its value, if that is not void, or "true" otherwise. #include <stdio.h> struct Foo { void operator()() {} }; struct Bar { bool operator()() { return false; } }; Foo foo; Bar bar; bool baz() { return false; } void bang() {} const char* print(bool b) { printf(b ? "true, " : "false, "); } template <typename Functor> bool magicCallFunction(Functor f) { return true; // lots of template magic occurs here... } int main(int argc, char** argv) { print(magicCallFunction(foo)); print(magicCallFunction(bar)); print(magicCallFunction(baz)); print(magicCallFunction(bang)); printf("\n"); }

  Read the article

< Previous Page | 303 304 305 306 307 308 309 310 311 312 313 314  | Next Page >