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  • Nested Routes and Parameters for Rails URLs (Best Practice)

    - by viatropos
    Hey there, I have a decent understanding of RESTful urls and all the theory behind not nesting urls, but I'm still not quite sure how this looks in an enterprise application, like something like Amazon, StackOverflow, or Google... Google has urls like this: http://code.google.com/apis/ajax/ http://code.google.com/apis/maps/documentation/staticmaps/ https://www.google.com/calendar/render?tab=mc Amazon like this: http://www.amazon.com/books-used-books-textbooks/b/ref=sa_menu_bo0?ie=UTF8&node=283155&pf_rd_p=328655101&pf_rd_s=left-nav-1&pf_rd_t=101&pf_rd_i=507846&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1PK4ZKN4YWJJ9B86ANC9 http://www.amazon.com/Ruby-Programming-Language-David-Flanagan/dp/0596516177/ref=sr_1_1?ie=UTF8&s=books&qid=1258755625&sr=1-1 And StackOverflow like this: http://stackoverflow.com/users/169992/viatropos http://stackoverflow.com/questions/tagged/html http://stackoverflow.com/questions/tagged?tagnames=html&sort=newest&pagesize=15 So my question is, what is best practice in terms of creating urls for systems like these? When do you start storing parameters in the url, when don't you? These big companies don't seem to be following the rules so hotly debated in the ruby community (that you should almost never nest URLs for example), so I'm wondering how you go about implementing your own urls in larger scale projects because it seems like the idea of not nesting urls breaks down at anything larger than a blog. Any tips?

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  • What is the recommended coding style for PowerShell?

    - by stej
    Is there any recommended coding style how to write PowerShell scripts? It's not about how to structure the code (how many functions, if to use module, ...). It's about 'how to write the code so that it is readable'. In programming languages there are some recommended coding styles (what to indent, how to indent - spaces/tabs, where to make new line, where to put braces,...), but I haven't seen any suggestion for PowerShell. What I'm interested particularly in: How to write parameters function New-XYZItem ( [string] $ItemName , [scriptblock] $definition ) { ... (I see that it's more like 'V1' syntax) or function New-PSClass { param([string] $ClassName ,[scriptblock] $definition )... or (why to add empty attribute?) function New-PSClass { param([Parameter()][string] $ClassName ,[Parameter()][scriptblock] $definition )... or (other formatting I saw maybe in Jaykul's code) function New-PSClass { param( [Parameter()] [string] $ClassName , [Parameter()] [scriptblock] $definition )... or ..? How to write complex pipeline Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc or (name of cmdlet on new line) Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc | and what if there are -begin -process -end params? how to make it the most readable? Get-SomeData -param1 abc -param2 xyz | % -begin { init } -process { Process-somehow2 ... } -end { Process-somehow3 ... } | % -begin { } .... or Get-SomeData -param1 abc -param2 xyz | % ` -begin { init } ` -process { Process-somehow2 ... } ` -end { Process-somehow3 ... } | % -begin { } .... the indentitation is important here and what element is put on new line as well. I have covered only questions that come on my mind very frequently. There are some others, but I'd like to keep this SO question 'short'. Any other suggestions are welcome.

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  • Cannot find interface declaration for 'UIResponder'

    - by lfe-eo
    Hi all, I am running into this issue when trying to compile code for an iPhone app that I inherited from a previous developer. I've poked around on a couple forums and it seems like the culprit may be a circular #import somewhere. First - Is there any easy way to find if this is the case/find what files the loop is in? Second - Its definitely possible this isn't the problem. This is the full error (truncated file paths so its easier to view here): In file included from [...]/Frameworks/UIKit.framework/Headers/UIView.h:9, from [...]/Frameworks/UIKit.framework/Headers/UIActivityIndicatorView.h:8, from [...]/Frameworks/UIKit.framework/Headers/UIKit.h:11, from /Users/wbs/Documents/EINetIPhone/EINetIPhone_Prefix.pch:13: [...]/Frameworks/UIKit.framework/Headers/UIResponder.h:15: error: expected ')' before 'UIResponder' [...]/Frameworks/UIKit.framework/Headers/UIResponder.h:17: error: expected '{' before '-' token [...]/Frameworks/UIKit.framework/Headers/UIResponder.h:42: warning: '@end' must appear in an @implementation context [...]/Frameworks/UIKit.framework/Headers/UIResponder.h:51: error: expected ':' before ';' token [...]/Frameworks/UIKit.framework/Headers/UIResponder.h:58: error: cannot find interface declaration for 'UIResponder' As you can see, there are other errors alongside this one. These seem to be simple syntax errors, however, they appear in one of Apple's UIKit files (not my own) so I am seriously doubting that Apple's code is truly producing these errors. I'm stumped as to how to solve this issue. If anyone has any ideas of things I could try or ways/places I could get more info on the problem, I'd really appreciate it. I'm very new to Obj-C and iPhone coding.

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  • Using Essential Use Cases to design a UI-centric Application

    - by Bruno Brant
    Hello all, I'm begging a new project (oh, how I love the fresh taste of a new project!) and we are just starting to design it. In short: The application is a UI that will enable users to model an execution flow (a Visio like drag & drop interface). So our greatest concern is usability and features that will help the users model fast and clearly the execution flow. Our established methodology makes extensive use of Use Cases in order to create a harmonious view of the application between the programmers and users. This is a business concern, really: I'd prefer to use an Agile Method with User Stories rather than User Cases, but we need to define a clear scope to sell the product to our clients. However, Use Cases have a number of flaws, most of which are related to the fact that they include technical details, like UI, etc, as can be seem here. But, since we can't use User Stories and a fully interactive design, I've decided that we compromise: I will be using Essential Use Cases in order to hide those details. Now I have another problem: it's essential (no pun intended) to have a clear description of UI interaction, so, how should I document it? In other words, how do I specify a application through the use of Essential Use Cases where the UI interaction is vital to it? I can see some alternatives: Abandon the use of Use Cases since they don't correctly represent the problem Do not include interface descriptions in the use case, but create another documentation (Story Boards) and link then to the Essential Use Cases Include UI interaction description to the Essential Use Cases, since they are part of the business rules in the perspective of the users and the application itself

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  • OleDBDataAdapter UNPIVOT Query not working with Microsoft.ACE.OLEDB.12.0 DataSource

    - by JayT
    I am reading in an excel file with an OleDBDataAdapter. I am using a select statement to UNPIVOT the data and insert into DataSet. However, the compiler is genereating this error: {"Syntax error in FROM clause."} But the SQL Statement is correct as I have used it in other DB's Here is the code: string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + FileName + ";Extended Properties=\"Excel 12.0 Xml;HDR=" + HDR + ";IMEX=1\""; OleDbConnection conn = new OleDbConnection(strConn); conn.Open(); string SQL = "select Packhouse, Rm, Quantity , Product " + " FROM " + " ( " + " SELECT Date,Packhouse, Rm,[FG XL], [FG L] " + " FROM [" + xlSheet + "] " + " ) Main " + " UNPIVOT " + " ( " + " Quantity FOR Product in ([FG XL], [FG L]) " + " ) Sub " + " WHERE (Date = '2010/03/08') and Quantity <> '0' and Packhouse = 'A' and Rm = '1' "; OleDbDataAdapter adapter = new OleDbDataAdapter(); adapter.SelectCommand = new OleDbCommand(SQL, conn); ds[sequencecounter] = new DataSet(); adapter.Fill(ds[sequencecounter], xlSheet); If I copy and paste the excel data into a DB, then the select query works, but the data presented to me is in excel spreadsheets. If anyone could provide help on this it will be much appreciated. Regards, J

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  • Publishing toolchain

    - by Marcelo de Moraes Serpa
    Hello all, I have a book project which I'd like to start sooner than later. This would follow an agile-like publishing workflow, i.e: publish early and often. It is meant to be self-publsihed by me and I'm not really looking to paper-publish it, even though we never know. If I weren't a geek, I'd probably have already started writting in Word or any other WYSIWYG tool and just export to PDF. However, we know it is not the best solution, and emacs rules my text-editing life, so, the output format should be as simple as possible and be text-based. I've thought about the following options: 1) Use orgmode and export to PDF; 2) Use markdown mode and export to PDF; 3) Use something similar to what the guys @ Pragmatic Progammers do: A XML + XSLT + LaTeX. More complex, but much more control over the style. Any other ideas / references ? I want to start writting as soon as possible. In fact, I already have a draft in an org-formatted file. However, I do want to have and use the full power of LaTex later on to format it the way I want and make it look fabulous :) Thanks in advance, Marcelo.

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  • Using an existing IQueryable to create a new dynamic IQueryable

    - by dnoxs
    I have a query as follows: var query = from x in context.Employees where (x.Salary > 0 && x.DeptId == 5) || x.DeptId == 2 order by x.Surname select x; The above is the original query and returns let's say 1000 employee entities. I would now like to use the first query to deconstruct it and recreate a new query that would look like this: var query = from x in context.Employees where ((x.Salary > 0 && x.DeptId == 5) || x.DeptId == 2) && (x,i) i % 10 == 0 order by x.Surname select x.Surname; This query would return 100 surnames. The syntax is probably incorrect, but what I need to do is attach an additional where clause and modify the select to a single field. I've been looking into the ExpressionVisitor but I'm not entirely sure how to create a new query based on an existing query. Any guidance would be appreciated. Thanks you.

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  • LINQ self referencing query

    - by Chris
    I have the following SQL query: select p1.[id], p1.[useraccountid], p1.[subject], p1.[message], p1.[views], p1.[parentid], case when p2.[created] is null then p1.[created] else p2.[created] end as LastUpdate from forumposts p1 left join ( select parentid, max(created) as [created] from forumposts group by parentid ) p2 on p2.parentid = p1.id where p1.[parentid] is null order by LastUpdate desc Using the following class: public class ForumPost : PersistedObject { public int Views { get; set; } public string Message { get; set; } public string Subject { get; set; } public ForumPost Parent { get; set; } public UserAccount UserAccount { get; set; } public IList<ForumPost> Replies { get; set; } } How would I replicate such a query in LINQ? I've tried several variations, but I seem unable to get the correct join syntax. Is this simply a case of a query that is too complicated for LINQ? Can it be done using nested queries some how? The purpose of the query is to find the most recently updated posts i.e. replying to a post would bump it to the top of the list. Replies are defined by the ParentID column, which is self-referencing.

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  • Trying to grab just absolute links from a webpage using BeautifulSoup

    - by Kevin
    I am reading the contents of a webpage using BeautifulSoup. What I want is to just grab the <a href> that start with http://. I know in beautifulsoup you can search by the attributes. I guess I am just having a syntax issue. I would imagine it would go something like. page = urllib2.urlopen("http://www.linkpages.com") soup = BeautifulSoup(page) for link in soup.findAll('a'): if link['href'].startswith('http://'): print links But that returns: Traceback (most recent call last): File "<stdin>", line 2, in <module> File "C:\Python26\lib\BeautifulSoup.py", line 598, in __getitem__ return self._getAttrMap()[key] KeyError: 'href' Any ideas? Thanks in advance. EDIT This isn't for any site in particular. The script gets the url from the user. So internal link targets would be an issue, that's also why I only want the <'a'> from the pages. If I turn it towards www.reddit.com, it parses the beginning links and it gets to this: <a href="http://www.reddit.com/top/">top</a> <a href="http://www.reddit.com/saved/">saved</a> Traceback (most recent call last): File "<stdin>", line 2, in <module> File "C:\Python26\lib\BeautifulSoup.py", line 598, in __getitem__ return self._getAttrMap()[key] KeyError: 'href'

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  • How to befriend a templated class's constructor?

    - by Kyle
    Why does class A; template<typename T> class B { private: A* a; public: B(); }; class A : public B<int> { private: friend B<int>::B<int>(); int x; }; template<typename T> B<T>::B() { a = new A; a->x = 5; } int main() { return 0; } result in ../src/main.cpp:15: error: invalid use of constructor as a template ../src/main.cpp:15: note: use ‘B::B’ instead of ‘B::class B’ to name the constructor in a qualified name yet changing friend B<int>::B<int>() to friend B<int>::B() results in ../src/main.cpp:15: error: no ‘void B::B()’ member function declared in class ‘B’ while removing the template completely class A; class B { private: A* a; public: B(); }; class A : public B { private: friend B::B(); int x; }; B::B() { a = new A; a->x = 5; } int main() { return 0; } compiles and executes just fine -- despite my IDE saying friend B::B() is invalid syntax?

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  • zend_form display group inside foreach

    - by Mike
    I want to create a display group generated from foreach() clause output. I can't seem to get the syntax correct. Here's the business logic: for each category row find the associated fees output the category description as a label and the fees as radio buttons then create a display group with the fees as the group elements and the category description as the legend. I then have a style sheet format the elements on the page. and here's the code: foreach ($categoryData as $categoryRow) { $fees[$i] = new Zend_Form_Element_Radio("fees[$i]"); $fees[$i]->setDescription(strval($categoryRow['description'])); foreach ($feeData as $feeRow) { if ($feeRow['categories_idCategory'] == $categoryRow['idCategory']){ $fees[$i] ->addMultiOption($feeRow['idFees'] . '-' . $feeRow['categories_idCategory'], $feeRow['amount'] . '-' . $feeRow['name']); } } $fees[$i]->setRequired(TRUE); $this->addElements(array($fees[$i])); $this->addDisplayGroup($feeRow['name'], 'feeGroup',array('legend' => strval($feeRow['description']))); $i++; } I tried placing the addDisplayGroup() code within the foreach(), but I get the error: Message: No valid elements specified for display group So, my guess is that I'm making some kind of novice mistake that you experts will spot right away. I appreciate your time and attention to this matter.

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  • dumping the source code for an anonymous function

    - by intuited
    I'm working with a lot of anonymous functions, ie functions declared as part of a dictionary, aka "methods". It's getting pretty painful to debug, because I can't tell what function the errors are happening in. Vim's backtraces look like this: Error detected while processing function NamedFunction..2111..2105: line 1: E730: using List as a String This trace shows that the error occurred in the third level down the stack, on the first line of anonymous function #2105. IE NamedFunction called anonymous function #2111, which called anonymous function #2105. NamedFunction is one declared through the normal function NamedFunction() ... endfunction syntax; the others were declared using code like function dict.func() ... endfunction. So obviously I'd like to find out which function has number 2105. Assuming that it's still in scope, it's possible to find out what Dictionary entry references it by dumping all of the dictionary variables that might contain that reference. This is sort of awkward and it's difficult to be systematic about it, though I guess I could code up a function to search through all of the loaded dictionaries for a reference to that function, watching out for circular references. Although to be really thorough, it would have to search not only script-local and global dictionaries, but buffer-local dictionaries as well; is there a way to access another buffer's local variables? Anyway I'm wondering if it's possible to dump the source code for the anonymous function instead. This would be a lot easier and probably more reliable.

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  • PartCover 2.5.3 win 7 x64

    - by user329814
    Could you tell me how you got PartCover running with VS2008 and win 7 x64? Based on this post http://stackoverflow.com/questions/256287/how-do-i-run-partcover-in-x64-windows, I ran c:\Program Files (x86)\Gubka Bob\PartCover .NET 2.3>CorFlags.exe PartCover.exe / 32BIT+ /Force with result Microsoft (R) .NET Framework CorFlags Conversion Tool. Version 3.5.21022.8 Copyright (c) Microsoft Corporation. All rights reserved. corflags : warning CF011 : The specified file is strong name signed. Using /Force will invalidate the signature of this image and will require the assembly to be resigned. and c:\Program Files (x86)\NUnit 2.5.2\bin\net-2.0>CorFlags.exe nunit.exe /32BIT+ /Force with result Microsoft (R) .NET Framework CorFlags Conversion Tool. Version 3.5.21022.8 Copyright (c) Microsoft Corporation. All rights reserved. Also, based on my discussion http://stackoverflow.com/questions/2546340/using-partcover-2-3-with-net-4-0-runtime/2964333#2964333, I also tried to use the x86 version of NUnit What I'm trying to run coverage for is the c# money sample for NUnit 2.5.2 I get the same System.Threading.ThreadInterruptedException --- System.Runtime.InteropServices.COMException (0x80040153): Retrieving the COM class factory for component with CLSID {FB20430E-CDC9-45D7-8453-272268002E08} failed due to the following error: 80040153 Thank you Edit: same thing with PartCover 2.2 My settings: exe file: C:\Program Files (x86)\NUnit 2.5.2\bin\net-2.0\nunit-console-x86.exe working dir: c:\Program Files (x86)\NUnit 2.5.2\samples\csharp\money\ work arg: /config=c:\Program Files (x86)\NUnit 2.5.2\samples\csharp\money\cs-money.csproj rules: +[]

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  • Shift-reduce: when to stop reducing?

    - by Joey Adams
    I'm trying to learn about shift-reduce parsing. Suppose we have the following grammar, using recursive rules that enforce order of operations, inspired by the ANSI C Yacc grammar: S: A; P : NUMBER | '(' S ')' ; M : P | M '*' P | M '/' P ; A : M | A '+' M | A '-' M ; And we want to parse 1+2 using shift-reduce parsing. First, the 1 is shifted as a NUMBER. My question is, is it then reduced to P, then M, then A, then finally S? How does it know where to stop? Suppose it does reduce all the way to S, then shifts '+'. We'd now have a stack containing: S '+' If we shift '2', the reductions might be: S '+' NUMBER S '+' P S '+' M S '+' A S '+' S Now, on either side of the last line, S could be P, M, A, or NUMBER, and it would still be valid in the sense that any combination would be a correct representation of the text. How does the parser "know" to make it A '+' M So that it can reduce the whole expression to A, then S? In other words, how does it know to stop reducing before shifting the next token? Is this a key difficulty in LR parser generation?

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  • Symfony / Doctrine - How to filter form field by property in related model

    - by Dan
    I have a UserForm class which has a select list populated from a related model (specified by a foreign relationship in the yml) like so: $this->setWidget('report_id', new sfWidgetFormDoctrineChoice(array('model' => $this->getRelatedModelName('Report')))); I'd like to filter the Report objects that come from this relation by one of the Report fields, "active" such that only Reports with active=1 appear in the form. I have a method, ReportTable::GetActiveReports() that performs the appropriate query and returns the filtered reports. So one option is to populate the Widget with the results of that function. Any tips on the syntax to do that? It seems to me the cleaner way is to use the UserFormFilter class to filter the reports by active=1 there. Unfortunately I couldn't find any documentation on how to use form filters (or really what they are), so maybe this is not the right solution. Is a Form Filter the appropriate tool for this job? It seems I should use the Doctrine_Record_Filter_Standard class as defined here: http://www.doctrine-project.org/api/orm/1.2/doctrine/doctrine_record_filter_standard.html But it's not clear to me the appropriate usage. Any guidance would be helpful. Thanks! Dan

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  • jQuery Validation Plugin: Validating Checkboxes with Different Names

    - by Michael
    I have a set of 4 checkboxes, all with different names, and require that at least 1 is checked. I know there are a few posts on here already trying to answer this question. The solution that seems to be most logical to me is the answer posted on Question 1734840, but I can't seem to get it working! What's wrong with my code? Or any other new coding ideas to get this working? I have set the class on all of them to 'require-one'. My jQuery code is $(document).ready(function(){ $("#itemForm").validate({ highlight: function(element, errorClass, validClass) { $(element).addClass(errorClass).removeClass(validClass); $(element.form).find("label[for=" + element.name + "]") .addClass("radioerror"); }, unhighlight: function(element, errorClass, validClass) { $(element).removeClass(errorClass).addClass(validClass); $(element.form).find("label[for=" + element.name + "]") .removeClass("radioerror"); }, rules: { 'require-one': { required : { depends: function(element) { var allBoxes = $('.require-one'); if (allBoxes.filter(':checked').length == 0) { if (allBoxes.eq(element).length != 0) { return true; } } return false; } } } , }, errorPlacement: function(error, element) { if ( element.is("#other_descrip") ) error.appendTo("#othererror" ); if ( element.is("#itemlist") ) error.appendTo("#itemerror" ); } }); });

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  • MVC2 and jquery.validate.js

    - by Will I Am
    I am experiencing some confusion with jquery.validate.js First of all, what is MicrosoftMvcJqueryValidation.js. It is referenced in snippets on the web but appears to have dissapeared from the RTM MVC2 and is now in futures. Do I need it? The reason I'm asking is that I'm trying to use the validator with MVC and I can't get it to work. I defined my JS as: $(document).ready(function () { $("#myForm").validate({ rules: { f_fullname: { required: true }, f_email: { required: true, email: true }, f_email_c: { equalTo: "#f_email" }, f_password: { required: true, minlength: 6 }, f_password_c: { equalTo: "#f_password" } }, messages: { f_fullname: { required: "* required" }, f_email: { required: "* required", email: "* not a valid email address" }, f_email_c: { equalTo: "* does not match the other email" }, f_password: { required: "* required", minlength: "password must be at least 6 characters long" }, f_password_c: { equalTo: "* does not match the other email" } } }); }); and my form on the view: <% using (Html.BeginForm("CreateNew", "Account", FormMethod.Post, new { id = "myForm" })) { %> <fieldset> <label for="f_fullname">name:</label><input id="f_fullname"/> <label for="f_email"><input id="f_email"/> ...etc... <input type="submit" value="Create" id="f_submit"/> </fieldset> <% } %> and the validation method gets called on .ready() with no errors in firebug. however when I submit the form, nothing gets validated and the form gets submitted. If I create a submitHandler() it gets called, but the plugin doesn't detect any validation errors (.valid() == true) What am I missing?

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  • WCF for a shared data access

    - by Audrius
    Hi all, I have a little experience with WCF and would like to get your opinion/suggestion on how the following problem can be solved: A web service needs to be accessible from multiple clients simultaneously and service needs to return a result from a shared data set. The concrete project I'm working on has to store a list of IP addresses/ranges. This list will be queried by a bunch of web servers for a validation purposes and we speak of a couple of thousand or more queries per minute. My initial draft approach was to use Windows service as a WCF host with service contract implementing class that is decorated with ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Multiple) that has a list object and a custom locking for accessing it. So basically I have a WCF service singleton with a list = shared data - multiple clients. What I do not like about it is that data and communication layers are merged into one and performance wise this doesn't feel "right". What I really really (- want is Windows service running an instance of IP list holding container class object, a second service running WCF service contract implementation and a way the latter querying the former in a nice way with a minimal blocking. Using another WCF channel would not really take me far away from the initial draft implementation or would it? What approach would you take? Project is still in a very early stage so complete design re-do is not out of question. All ideas are appreciated. Thanks! UPDATE: The data set will be changed dynamically. Web service will have a separate method to add IP or IP range and on top of that there will be a scheduled task that will trigger data cleanup every 10-15 minutes according to some rules. UPDATE 2: a separate benchmark project will be kicked up that should use MSSQL as a data backend (instead on in-memory list).

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  • Settings variable values in a Moq Callback() call

    - by Adam Driscoll
    I think I may be a bit confused on the syntax of the Moq Callback methods. When I try to do something like this: IFilter filter = new Filter(); List<IFoo> objects = new List<IFoo> { new Foo(), new Foo() }; IQueryable myFilteredFoos = null; mockObject.Setup(m => m.GetByFilter(It.IsAny<IFilter>())).Callback( (IFilter filter) => myFilteredFoos = filter.FilterCollection(objects)).Returns(myFilteredFoos.Cast<IFooBar>()); This throws a exception because myFilteredFoos is null during the Cast<IFooBar>() call. Is this not working as I expect? I would think FilterCollection would be called and then myFilteredFoos would be non-null and allow for the cast. FilterCollection is not capable of returning a null which draws me to the conclusion it is not being called. Also, when I declare myFilteredFoos like this: Queryable myFilteredFoos; The Return call complains that myFilteredFoos may be used before it is initialized.

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  • Database structure - is mySQL the right choice?

    - by Industrial
    Hi everyone, We are currently planning the database structure of a quite complex e-commerce web app that has flexibility as it's main cornerstone. Our app features a large amount of data (products) and we have run into a slight headache trying to keep performance high without compromizing normalization rules in the database, or leaving our highly beloved flexibility concept behind when integrating product options (also widely known as product attributes or parameters). Based on various references and sources available, we have made up lists on pros and cons of all major and well known database patterns to solve this. After comparing these, we have come up with two final alternatives: EAV (Entity-attribute-value model) : Pros: Database is used for all sorting. Cons: All related queries will include a number of joins between multiple tables in order to complete the collection of data. SLOB (Serialized LOB, also known as Facade?) : Pros: Very flexible. Keeping the number of necessary joins low compared to a EAV design pattern. Easy to update/add/remove data from each product. Cons: All sorting will be done by the application instead of the database. Will use lots of performance (memory?) when big datasets is processed by a large number of users. Our main questions: Which pattern/structure would you use, or maybe even a different solution? Is there better databases besides mySQL available nowadays to accomplish what we want? Thanks a lot! Reference: http://stackoverflow.com/questions/695752/product-table-many-kinds-of-product-each-product-has-many-parameters

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  • T-SQL Right Joins to ALL Entries inc Selected Column

    - by Pace
    Hi Experts, I have the following Query which produces the output below; SELECT TBLUSERS.USERID, TBLUSERS.ADusername, TBLACCESSLEVELS.ACCESSLEVELID, TBLACCESSLEVELS.AccessLevelName FROM TBLACCESSLEVELS INNER JOIN TBLACCESSRIGHTS ON TBLACCESSLEVELS.ACCESSLEVELID = TBLACCESSRIGHTS.ACCESSLEVELID INNER JOIN TBLUSERS ON TBLACCESSRIGHTS.USERID = TBLUSERS.USERID The output is this; 29 administrator 1 AllUsers 29 administrator 2 JobQueue 29 administrator 3 Telephone Directory Admin 29 administrator 4 Jobqueueadmin 29 administrator 5 UserAdmin 29 administrator 6 Product System 27 alan 1 AllUsers 97 andy 1 AllUsers 26 barry 1 AllUsers 26 barry 2 JobQueue 26 barry 3 Telephone Directory Admin 26 barry 4 Jobqueueadmin 26 barry 5 UserAdmin 26 barry 6 Product System 26 barry 7 Newseditor 26 barry 8 GreetingBoard What I would like to do is modify the query so I get all Access Levels regardless of weather there is an entry for that user. What I would also like to do is some sort of exist case so that I get output like the following; 29 administrator 1 AllUsers True 29 administrator 2 JobQueue True 29 administrator 3 Telephone Directory Admin True 29 administrator 4 Jobqueueadmin True 29 administrator 5 UserAdmin True 29 administrator 6 Product System True 29 administrator 7 Newseditor False 29 administrator 8 GreetingBoard False 27 alan 1 AllUsers True 27 alan 2 JobQueue False 27 alan 3 Telephone Directory Admin False 27 alan 4 Jobqueueadmin False 27 alan 5 UserAdmin False 27 alan 6 Product System False 27 alan 7 Newseditor False 27 alan 8 GreetingBoard False 97 andy 1 AllUsers True 97 andy 2 JobQueue False 97 andy 3 Telephone Directory Admin False 97 andy 4 Jobqueueadmin False 97 andy 5 UserAdmin False 97 andy 6 Product System False 97 andy 7 Newseditor False 97 andy 8 GreetingBoard False 26 Barry 1 AllUsers True 26 Barry 2 JobQueue True 26 Barry 3 Telephone Directory Admin True 26 Barry 4 Jobqueueadmin True 26 Barry 5 UserAdmin True 26 Barry 6 Product System True 26 Barry 7 Newseditor True 26 Barry 8 GreetingBoard True ......................................... So the rules are ALWAYS show ALL Entries for ACCESSLEVELS and where EXISTS in ACCESSRIGHTS produce a true / false to show this. I hope this makes sense and hopefully you dont need the table definitions as everything I need to work with is in the original Query. I just need a way of manipulating it slightly and getting the join in the right place. Thank you. Pace

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  • Hidden features of Perl?

    - by Adam Bellaire
    What are some really useful but esoteric language features in Perl that you've actually been able to employ to do useful work? Guidelines: Try to limit answers to the Perl core and not CPAN Please give an example and a short description Hidden Features also found in other languages' Hidden Features: (These are all from Corion's answer) C# Duff's Device Portability and Standardness Quotes for whitespace delimited lists and strings Aliasable namespaces Java Static Initalizers JavaScript Functions are First Class citizens Block scope and closure Calling methods and accessors indirectly through a variable Ruby Defining methods through code PHP Pervasive online documentation Magic methods Symbolic references Python One line value swapping Ability to replace even core functions with your own functionality Other Hidden Features: Operators: The bool quasi-operator The flip-flop operator Also used for list construction The ++ and unary - operators work on strings The repetition operator The spaceship operator The || operator (and // operator) to select from a set of choices The diamond operator Special cases of the m// operator The tilde-tilde "operator" Quoting constructs: The qw operator Letters can be used as quote delimiters in q{}-like constructs Quoting mechanisms Syntax and Names: There can be a space after a sigil You can give subs numeric names with symbolic references Legal trailing commas Grouped Integer Literals hash slices Populating keys of a hash from an array Modules, Pragmas, and command-line options: use strict and use warnings Taint checking Esoteric use of -n and -p CPAN overload::constant IO::Handle module Safe compartments Attributes Variables: Autovivification The $[ variable tie Dynamic Scoping Variable swapping with a single statement Loops and flow control: Magic goto for on a single variable continue clause Desperation mode Regular expressions: The \G anchor (?{}) and '(??{})` in regexes Other features: The debugger Special code blocks such as BEGIN, CHECK, and END The DATA block New Block Operations Source Filters Signal Hooks map (twice) Wrapping built-in functions The eof function The dbmopen function Turning warnings into errors Other tricks, and meta-answers: cat files, decompressing gzips if needed Perl Tips See Also: Hidden features of C Hidden features of C# Hidden features of C++ Hidden features of Java Hidden features of JavaScript Hidden features of Ruby Hidden features of PHP Hidden features of Python

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  • Decisions in teaching someone else to program: language selection

    - by Dinah
    My friend would like for me to guide her into learning programming. She's already proven enormous aptitude for thinking like a programmer but is scared of the idea of programming since in her mind it's relegated to some magical realm accessible only to smart people and trained computer scientists (ironically, I am neither but that's beside the point). My main question is the age-old and irritating question: which language should I chose? I've limited it down to these: PHP: dead simple to start with and I remember enough of the language to answer all novice questions. However, I can think of a million reasons why I wouldn't recommend this as a first language. The most diplomatic of which is that there's no desktop app option to which I would feel comfortable subjecting a novice. Python: supposed to be wonderful for beginners and generally everything I've heard about it screams that this is the correct choice. That's the problem: everything I've heard about it. I don't know it yet and have a lot of projects going on right now so I don't feel like learning it yet -- but I'm going to be the tech-support when any little thing goes wrong. I know there are tons of online resources but in the frustration of the moment, it's always going to be just me. C#: this is the language I'm most comfortable with so I know I can be good tech support. I also love this language and its versatility and community. The big drawback here is that I remember when I first learned it after doing mainly PHP, Perl, and JavaScript and I found the experience overwhelming. You are simultaneously learning: programming concepts, C# syntax, strong typing, OOP, and a complex powerful IDE with a bazillion options and buttons all over it.

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  • overriding enumeration base type using pragma or code change

    - by vprajan
    Problem: I am using a big C/C++ code base which works on gcc & visual studio compilers where enum base type is by default 32-bit(integer type). This code also has lots of inline + embedded assembly which treats enum as integer type and enum data is used as 32-bit flags in many cases. When compiled this code with realview ARM RVCT 2.2 compiler, we started getting many issues since realview compiler decides enum base type automatically based on the value an enum is set to. http://www.keil.com/support/man/docs/armccref/armccref_Babjddhe.htm For example, Consider the below enum, enum Scale { TimesOne, //0 TimesTwo, //1 TimesFour, //2 TimesEight, //3 }; This enum is used as a 32-bit flag. but compiler optimizes it to unsigned char type for this enum. Using --enum_is_int compiler option is not a good solution for our case, since it converts all the enum's to 32-bit which will break interaction with any external code compiled without --enum_is_int. This is warning i found in RVCT compilers & Library guide, The --enum_is_int option is not recommended for general use and is not required for ISO-compatible source. Code compiled with this option is not compliant with the ABI for the ARM Architecture (base standard) [BSABI], and incorrect use might result in a failure at runtime. This option is not supported by the C++ libraries. Question How to convert all enum's base type (by hand-coded changes) to use 32-bit without affecting value ordering? enum Scale { TimesOne=0x00000000, TimesTwo, // 0x00000001 TimesFour, // 0x00000002 TimesEight, //0x00000003 }; I tried the above change. But compiler optimizes this also for our bad luck. :( There is some syntax in .NET like enum Scale: int Is this a ISO C++ standard and ARM compiler lacks it? There is no #pragma to control this enum in ARM RVCT 2.2 compiler. Is there any hidden pragma available ?

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  • javascript form validation - positioning

    - by Holian
    Dear Masters! I have little snippet for validatin' my form. I need help to position the error messages, because now all message appear in the filed, so the user can't see it, and so its very annoying. $(document).ready(function() { jQuery.validator.addMethod("lettersonly", function(value, element) { return this.optional(element) || /^[a-zoöüóúéáuí ]+$/i.test(value); }, "<?php echo $lettersonly; ?>"); $("#regval").validate({ rules: { name: { required: true, minlength: 5, maxlength:30, lettersonly: true }, nick: { required: true, minlength: 3, maxlength:12 }, pass1: { required: true, minlength: 5 }, pass2: { required: true, minlength: 5, equalTo: "#pass1" }, messages: { full: { required: ".....", minlength: "....", maxlength: "...." }, nick: { required: "....", minlength: "....", maxlength: "...." }, pass1: { required: "....", minlength: "..." }, pass2: { required: "....", minlength: "....", equalTo: "...." }, }); }); </script>

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