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  • C++ converting back and forth from derived and base classes

    - by user127817
    I was wondering if there is a way in C++ to accomplish the following: I have a base class called ResultBase and two class that are Derived from it, Variable and Expression. I have a few methods that do work on vector<ResultBase> . I want to be able to pass in vectors of Variable and Expression into these methods. I can achieve this by creating a vector<ResultBase> and using static_cast to fill it with the members from my vector of Variable/Expression. However, once the vector has run through the methods, I want to be able to get it back as the vector of Result/Expression. I'll know for sure which one I want back. static_cast won't work here as there isn't a method to reconstruct a Variable/Expression from a ResultBase, and more importantly I wouldn't have the original properties of the Variables/Expressions The methods modify some of the properties of the ResultBase and I need those changes to be reflected in the original vectors. (i.e. ResultBase has a property called IsLive, and one of the methods will modify this property. I want this IsLive value to be reflected in the derived class used to create the ResultBase Whats the easiest way to accomplish this?

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  • User defined literal arguments are not constexpr?

    - by Pubby
    I'm testing out user defined literals. I want to make _fac return the factorial of the number. Having it call a constexpr function works, however it doesn't let me do it with templates as the compiler complains that the arguments are not and cannot be constexpr. I'm confused by this - aren't literals constant expressions? The 5 in 5_fac is always a literal that can be evaluated during compile time, so why can't I use it as such? First method: constexpr int factorial_function(int x) { return (x > 0) ? x * factorial_function(x - 1) : 1; } constexpr int operator "" _fac(unsigned long long x) { return factorial_function(x); // this works } Second method: template <int N> struct factorial { static const unsigned int value = N * factorial<N - 1>::value; }; template <> struct factorial<0> { static const unsigned int value = 1; }; constexpr int operator "" _fac(unsigned long long x) { return factorial_template<x>::value; // doesn't work - x is not a constexpr }

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  • What good open source programs exist for fuzzing popular image file types?

    - by JohnnySoftware
    I am looking for a free, open source, portable fuzzing tool for popular image file types that is written in either Java, Python, or Jython. Ideally, it would accept specifications for the fuzzable fields using some kind of declarative constraints. Non-procedural grammar for specifying constraints are greatly preferred. Otherwise, might as well write them all in Python or whatever. Just specifying ranges of valid values or expressions for them. Ideally, it would support some kind of generative programming to export the fuzzer into various programming languages to suit cases where more customization was required. If it supported a direct-manipulation GUI for controlling parameter values and ranges, that would be nice too. The file formats that should be supported are: GIF JPEG PNG So basically, it should be sort of a toolkit consisting of ready-to-run utility, a framework or library, and be capable of generating the fuzzed files directly as well as from programs it generates. It needs to be simple so that test images can be created quickly. It should have a batch capability for creating a series of images. Creating just one at a time would be too painful. I do not want a hacking tool, just a QA tool. Basically, I just want to address concerns that it is taking too long to get commonplace image rendering/parsing libraries stable and trustworthy.

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  • How can I pass in a params of Expression<Func<T, object>> to a method?

    - by Pure.Krome
    Hi folks, I have the following two methods :- public static IQueryable<T> IncludeAssociations<T>(this IQueryable<T> source, params string[] associations) { ... } public static IQueryable<T> IncludeAssociations<T>(this IQueryable<T> source, params Expression<Func<T, object>>[] expressions) { ... } Now, when I try and pass in a params of Expression<Func<T, object>>[], it always calls the first method (the string[]' and of course, that value isNULL`) Eg. Expression<Func<Order, object>> x1 = x => x.User; Expression<Func<Order, object>> x2 = x => x.User.Passport; var foo = _orderRepo .Find() .IncludeAssociations(new {x1, x2} ) .ToList(); Can anyone see what I've done wrong? Why is it thinking my params are a string? Can I force the type, of the 2x variables?

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  • Memory management of objects returned by methods (iOS / Objective-C)

    - by iOSNewb
    I am learning Objective-C and iOS programming through the terrific iTunesU course posted by Stanford (http://www.stanford.edu/class/cs193p/cgi-bin/drupal/) Assignment 2 is to create a calculator with variable buttons. The chain of commands (e.g. 3+x-y) is stored in a NSMutableArray as "anExpression", and then we sub in random values for x and y based on an NSDictionary to get a solution. This part of the assignment is tripping me up: The final two [methods] “convert” anExpression to/from a property list: + (id)propertyListForExpression:(id)anExpression; + (id)expressionForPropertyList:(id)propertyList; You’ll remember from lecture that a property list is just any combination of NSArray, NSDictionary, NSString, NSNumber, etc., so why do we even need this method since anExpression is already a property list? (Since the expressions we build are NSMutableArrays that contain only NSString and NSNumber objects, they are, indeed, already property lists.) Well, because the caller of our API has no idea that anExpression is a property list. That’s an internal implementation detail we have chosen not to expose to callers. Even so, you may think, the implementation of these two methods is easy because anExpression is already a property list so we can just return the argument right back, right? Well, yes and no. The memory management on this one is a bit tricky. We’ll leave it up to you to figure out. Give it your best shot. Obviously, I am missing something with respect to memory management because I don't see why I can't just return the passed arguments right back. Thanks in advance for any answers!

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  • What features are heavily used in C# 2.0, but is not available in VBNET 2.0, and how to workaround?

    - by Will Marcouiller
    I don't want a war between VBNET and C# developpers, neither is my goal to open a C# VS VBNET confrontation. I would like you all to list a feature that is heavily used in C#, but is not available in VBNET 2.0, and how would you work around to achieve a similar behaviour or purpose? For example: C# Accepts void (return) lambda expressions. Here's an example with FNH mapping: Component(x => x.Address, m => { m.Map(x => x.Number); m.Map(x => x.Street); m.Map(x => x.PostCode); }); This is impossible to do before VBNET 4.0 (supposed to be doable in VBNET 4.0) VBNET Must write a helping method (Sub), and provide the AddressOf this method in order to workaround. Private Sub Helper(ByVal m As MType) m.Map(Function(x) x.Number) m.Map(Function(x) x.Street) m.Map(Function(x) x.PostCode) End Sub ... Component(Function(x) x.Address, AddressOf Helper) Now I know, it is not VBNET 2.0, but this is an example. VBNET 3.0 and 3.5 can used too. Please just mention what version of VBNET this refers to.

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  • Use of RegularExpressionValidator in MS .Net Framework

    - by Lawk Salih
    Hi- I am trying to use the RegularExpressionValidator Control in Visual Studio to validate a textbox for email address expressions. Here's my code (very basic) Email:&nbsp; <input id="Text1" type="text" /><br /> <br /> <input id="Validate" type="button" value="Validate" runat="server" /><br /> <br /> <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ErrorMessage="RegularExpressionValidator" ControlToValidate="Validate" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"></asp:RegularExpressionValidator> Now, when I set controlToValidate to Validate, I get the following error message: Server Error in '/' Application. Control 'Validate' referenced by the ControlToValidate property of 'RegularExpressionValidator1' cannot be validated. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Web.HttpException: Control 'Validate' referenced by the ControlToValidate property of 'RegularExpressionValidator1' cannot be validated. Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [HttpException (0x80004005): Control 'Validate' referenced by the ControlToValidate property of 'RegularExpressionValidator1' cannot be validated.] System.Web.UI.WebControls.BaseValidator.CheckControlValidationProperty(String name, String propertyName) +8734357 System.Web.UI.WebControls.BaseValidator.ControlPropertiesValid() +40 System.Web.UI.WebControls.BaseValidator.get_PropertiesValid() +21 System.Web.UI.WebControls.BaseValidator.OnPreRender(EventArgs e) +27 System.Web.UI.Control.PreRenderRecursiveInternal() +80 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Control.PreRenderRecursiveInternal() +171 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +842 Version Information: Microsoft .NET Framework Version:2.0.50727.3607; ASP.NET Version:2.0.50727.3082 I have tried the same mechanism before and have worked; however, this time I am on a new machine, WinXP Pro running IIS v5.1. Any direction would be appreciated.

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  • Searching Natural Language Sentence Structure

    - by Cerin
    What's the best way to store and search a database of natural language sentence structure trees? Using OpenNLP's English Treebank Parser, I can get fairly reliable sentence structure parsings for arbitrary sentences. What I'd like to do is create a tool that can extract all the doc strings from my source code, generate these trees for all sentences in the doc strings, store these trees and their associated function name in a database, and then allow a user to search the database using natural language queries. So, given the sentence "This uploads files to a remote machine." for the function upload_files(), I'd have the tree: (TOP (S (NP (DT This)) (VP (VBZ uploads) (NP (NNS files)) (PP (TO to) (NP (DT a) (JJ remote) (NN machine)))) (. .))) If someone entered the query "How can I upload files?", equating to the tree: (TOP (SBARQ (WHADVP (WRB How)) (SQ (MD can) (NP (PRP I)) (VP (VB upload) (NP (NNS files)))) (. ?))) how would I store and query these trees in a SQL database? I've written a simple proof-of-concept script that can perform this search using a mix of regular expressions and network graph parsing, but I'm not sure how I'd implement this in a scalable way. And yes, I realize my example would be trivial to retrieve using a simple keyword search. The idea I'm trying to test is how I might take advantage of grammatical structure, so I can weed-out entries with similar keywords, but a different sentence structure. For example, with the above query, I wouldn't want to retrieve the entry associated with the sentence "Checks a remote machine to find a user that uploads files." which has similar keywords, but is obviously describing a completely different behavior.

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  • Why is my Scala function returning type Unit and not whatever is the last line?

    - by Andy
    I am trying to figure out the issue, and tried different styles that I have read on Scala, but none of them work. My code is: .... val str = "(and x y)"; def stringParse ( exp: String, pos: Int, expreshHolder: ArrayBuffer[String], follow: Int ) var b = pos; //position of where in the expression String I am currently in val temp = expreshHolder; //holder of expressions without parens var arrayCounter = follow; //just counts to make sure an empty spot in the array is there to put in the strings if(exp(b) == '(') { b = b + 1; while(exp(b) == ' '){b = b + 1} //point of this is to just skip any spaces between paren and start of expression type if(exp(b) == 'a') { temp(arrayCounter) = exp(b).toString; b = b+1; temp(arrayCounter)+exp(b).toString; b = b+1; temp(arrayCounter) + exp(b).toString; arrayCounter+=1} temp; } } val hold: ArrayBuffer[String] = stringParse(str, 0, new ArrayBuffer[String], 0); for(test <- hold) println(test); My error is: Driver.scala:35: error: type mismatch; found : Unit required: scala.collection.mutable.ArrayBuffer[String] ho = stringParse(str, 0, ho, 0); ^one error found When I add an equals sign after the arguments in the method declaration, like so: def stringParse ( exp: String, pos: Int, expreshHolder: ArrayBuffer[String], follow: Int ) ={....} It changes it to "Any". I am confused on how this works. Any ideas? Much appreciated.

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  • IP Address Validation Help

    - by Zubair1
    I am using this IP Validation Function that I came across while browsing, it has been working well until today i ran into a problem. For some reason the function won't validate this IP as valid: 203.81.192.26 I'm not too great with regular expressions, so would appreciate any help on what could be wrong. If you have another function, I would appreciate if you could post that for me. The code for the function is below: public static function validateIpAddress($ip_addr) { global $errors; $preg = '#^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}' . '(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$#'; if(preg_match($preg, $ip_addr)) { //now all the intger values are separated $parts = explode(".", $ip_addr); //now we need to check each part can range from 0-255 foreach($parts as $ip_parts) { if(intval($ip_parts) > 255 || intval($ip_parts) < 0) { $errors[] = "ip address is not valid."; return false; } return true; } return true; } else { $errors[] = "please double check the ip address."; return false; } }

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  • Rebuilding old (2010) django project in 2012

    - by birgit
    I am trying to make an old Django project run again. After seemingly having solved issues with old sorl.thumbnail versions and deprecated expressions I now get this error when running python manage.py runserver I also tried to copy & paste my old files into a new Django project and get the exactly same error. Maybe someone here has a clue where the problem lies? Unhandled exception in thread started by <bound method Command.inner_run of <django.contrib.staticfiles.management.commands.runserver.Command object at 0x2a80510>> Traceback (most recent call last): File "/usr/lib/python2.7/dist-packages/django/core/management/commands/runserver.py", line 88, in inner_run self.validate(display_num_errors=True) File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 249, in validate num_errors = get_validation_errors(s, app) File "/usr/lib/python2.7/dist-packages/django/core/management/validation.py", line 35, in get_validation_errors for (app_name, error) in get_app_errors().items(): File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 146, in get_app_errors self._populate() File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 61, in _populate self.load_app(app_name, True) File "/usr/lib/python2.7/dist-packages/django/db/models/loading.py", line 78, in load_app models = import_module('.models', app_name) File "/usr/lib/python2.7/dist-packages/django/utils/importlib.py", line 35, in import_module __import__(name) File "/home/me/Documents/wdws/wdws/../wdws/cityofwindows/models.py", line 73, in <module> class Image(models.Model): File "/home/me/Documents/wdws/wdws/../wdws/cityofwindows/models.py", line 83, in Image 'large': {'size': (640, 640)}, File "/usr/lib/python2.7/dist-packages/django/db/models/fields/files.py", line 233, in __init__ super(FileField, self).__init__(verbose_name, name, **kwargs) TypeError: __init__() got an unexpected keyword argument 'extra_thumbnails' I need to re-build the project just for visual documentation locally... so also any hints on how to quickly re-run outdated django-projects are very welcome!! Thanks a lot (using Ubuntu 12.04)

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  • Is it possible to split HTML using DOMDocument?

    - by Lynn Adrianna
    Using DOMDocument, is it possible to split a block of HTML by text wrapped in tags and those that are not, while maintaining the order? Sorry, if this doesn't make sense. My example should make it clear. Let's say I have the following block of HTML: text1<b style="color:pink">text2</b>text3<b>text4</b> <b style="font-weight:bold">text5</b> Is it possible create an array as such: array( [0] => text1 [1] => <b style="color:pink">text2</b> [2] => text3 [3] => <b>text4</b> [4] => [5] => <b style="font-weight:bold">text5</b> ) Below is my current working solution, which uses a regular expression, to split the HTML. $tokens = preg_split('/(<b\b[^>]*>.*?<\/b>)/i', $html, null, PREG_SPLIT_DELIM_CAPTURE); However, I always read that it is a bad idea to parse HTML using regular expressions, so was just wondering if there is a better way.

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  • How to emulate mod_rewrite in PHP

    - by Tyler Crompton
    I have a few URLs that I want to map to certain files via PHP. Currently, I am just using mod_rewrite in Apache. However, my application is getting too large for the rewriting to be done with regular expressions. So I created a file router.php that does the rewriting. I understand to do a redirect I could just send the Location: header. However, I don't always want to do a redirect. For example, I may want /api/item/ to map to the file /herp/derp.php relative to the document root. I need to preserve the HTTP method as well. "No problem," I thought. I made my .htaccess have the following snippet. RewriteEngine On RewriteRule ^api/item/$ /cgi-bin/router.php [L] And my router.php file looks as follows: <?php $uri = parse_url($_SERVER['REQUEST_URI']); $query = isset($uri['query']) ? $uri['query'] ? array(); // some code that modifies the query require_once "{$_SERVER['DOCUMENT_ROOT']}/herp/derp.php?" . http_build_query($query); ?> However, this doesn't work, because the OS is looking for a file named derp.php?some=query. How can I simulate a rewrite rule such as RewriteRule ^api/item/$ /herp/derp/ [L] in PHP. In other words, how do I tell the server to process a different URL than requested and preserve the query and HTTP method without causing a redirect? Note: Using variables set in router.php is less than desirable and is bad structure since it's only supposed to be responsible for handling URLs. I am open to using a light-weight third party solution.

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  • How to extract ALL typedefs and structs and unions from c++ source

    - by Michael Wells
    I have inherited a Visual Studio project that contains hundreds of files. I would like to extract all the typedefs, structs and unions from each .h/.cpp file and put the results in a file). Each typdef/struct/union should be on one line in the results file. This would make sorting much easier. typdef int myType; struct myFirstStruct { char a; int b;...}; union Part_Number_Serial_Number_Part_2_Response_Message_Type {struct{Message_Response_Head_Type Head; Part_Num_Serial_Num_Part_2_Report_Array Part_2_Report; Message_Tail_Type Tail;} Data; BYTE byData[140];}myUnion; struct { bool c; int d;...}mySecondStruct; My problem is, I do not know what to look for (grammar of typedef/structs/unions) using a regular expression. I cannot believe that nobody has done this before (I googled and have not found anything on this). Does anyone know the regular expressions for these? (Note some are commented out using // others /* */) Or a tool to accomplish this. Edit: I am toying with the idea of autogenerating source code and/or dialogs for modifying messages that use the underlying typedef/struct/union. I was going to use the output to generate an XML file that could be used for this reason. The source for these are in C/C++ and used in almost all my projects. These projects are usually NOT in C/C++. By using the XML version I would only need to update/add the typedef/struct/union only in one place and all the projects would be able to autogen the source and/or dialogs.

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  • Regular Expression with Names and Emails

    - by Nina
    I am having a problem with regular expressions at the moment. What I'm trying to do is that for each line through the iteration, it checks for this type of pattern: Lastname, Firstname If it finds the name, then it will take the first letter of the first name, and the first six letters of the lastname and form it as an email. I have the following: $checklast = "[A-z],"; $checkfirst = "[A-z]"; if (ereg($checklast, $parts[1])||ereg($checkfirst, $parts[2])){ $first = preg_replace($checkfirst, $checkfirst{1,1}, $parts[2]); print "<a href='mailto:[email protected];'> $parts[$i] </a>"; } This one obviously broke the code. But I was initially attempting to find only the first letter of the firstname and then after that the first six letters of the lastname followed by the @email.com This didn't work out too well. I'm not sure what to do at this point. Any help is much appreciated.

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  • How to cache code in PHP?

    - by Janis Peisenieks
    I am creating a custom form building system, which includes various tokens. These tokens are found using Regular Expressions, and depending on the type of toke, parsed. Some require simple replacement, some require cycles, and so forth. Now I know, that RegExp is quite resource and time consuming, so I would like to be able to parse the code for the form once, creating a php code, and then save the PHP code, for next uses. How would I go about doing this? So far I have only seen output caching. Is there a way to cache commands like echo and cycles like foreach()? Because of misunderstandings, I'll create an example. Unparsed template data: Thank You for Your interest, [*Title*] [*Firstname*] [*Lastname*]. Here are the details of Your order! [*KeyValuePairs*] Here is the link to Your request: [*LinkToRequest*]. Parsed template: "Thank You for Your interest, <?php echo $data->title;?> <?php echo $data->firstname;?> <?php echo $data->lastname;?>. Here are the details of Your order! <?php foreach($data->values as $key=>$value){ echo $key."-".$value }?> Here is the link to Your request: <?php echo $data->linkToRequest;?>. I would then save the parsed template, and instead of parsing the template every time, just pass the $data variable to the already parsed one, which would generate an output.

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  • WPF DataGrid populating blank rows on TreeView's SelectedItemChanged

    - by jes9582
    When my DataGrid populates on the TreeView's SelectedItemChanged event it finds the objects and creates the rows accordingly but the rows populate with no text or are just blank. So I know it is finding my objects but it is not displaying them properly. Does anyone see where I made an error or suggest any changes or fixes? Thank you in advance! Here is the CSharp code that is setting the DataGrid's ItemsSource (I am using .dbml and LINQ with Lambda expressions): dgSystemSettings.ItemsSource = (tvSystemConfiguration.SelectedItem as SYSTEM_SETTINGS_GROUP).SYSTEM_SETTINGS_NAMEs.Join(ssdc.SYSTEM_SETTINGS_VALUEs, x => x.SSN_ID, y => y.SSV_SSN_ID, (x, y) => new { SYSTEM_SETTINGS_NAME = x, SYSTEM_SETTINGS_VALUE = y }); And here is the .xaml: <DataGrid Name="dgSystemSettings" AutoGenerateColumns="False" Height="447" Width="513" DockPanel.Dock="Right" ItemsSource="{Binding}" VerticalAlignment="Top" Margin="10,10,0,0"> <DataGrid.Columns> <DataGridTextColumn x:Name="colDisplayName" Header="Name" Binding="{Binding SSN_DISPLAY_NAME}"></DataGridTextColumn> <DataGridTextColumn x:Name="colValue" Header="Value" Binding="{Binding SSV_VALUE}"></DataGridTextColumn> </DataGrid.Columns> </DataGrid>

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  • Comparison of Java and .NET technologies/frameworks

    - by Paul Sasik
    I work in a shop that is a mix of mostly Java and .NET technologists. When discussing new solutions and architectures we often encounter impedance in trying to compare the various technologies, frameworks, APIs etc. in use between the two camps. It seems that each camp knows little about the other and we end up comparing apples to oranges and forgetting about the bushels. While researching the topic I found this: Java -- .Net rough equivalents It's a nice list but it's not quite exhaustive and is missing the key .NET 3.0 technologies and a few other tidbits. To complete that list: what are the near/rough equivalents (or a combination of technologies) in Java to the following in .NET? WCF WPF Silverlight = JavaFx WF = jBMP (Java Business Process Management) Generics Lambda expressions = lambdaJ project or Closures Linq (not Linq-to-SQL) ...have i missed anything else? Note that I omitted technologies that are already covered in the linked article. I would also like to hear feedback on whether the linked article is accurate. Thanks. (Will CW if requested.)

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  • Strongly typed dynamic Linq sorting

    - by David
    I'm trying to build some code for dynamically sorting a Linq IQueryable<. The obvious way is here, which sorts a list using a string for the field name http://dvanderboom.wordpress.com/2008/12/19/dynamically-composing-linq-orderby-clauses/ However I want one change - compile time checking of field names, and the ability to use refactoring/Find All References to support later maintenance. That means I want to define the fields as f=f.Name, instead of as strings. For my specific use I want to encapsulate some code that would decide which of a list of named "OrderBy" expressions should be used based on user input, without writing different code every time. Here is the gist of what I've written: var list = from m Movies select m; // Get our list var sorter = list.GetSorter(...); // Pass in some global user settings object sorter.AddSort("NAME", m=m.Name); sorter.AddSort("YEAR", m=m.Year).ThenBy(m=m.Year); list = sorter.GetSortedList(); ... public class Sorter ... public static Sorter GetSorter(this IQueryable source, ...) The GetSortedList function determines which of the named sorts to use, which results in a List object, where each FieldData contains the MethodInfo and Type values of the fields passed in AddSort: public SorterItem AddSort(Func field) { MethodInfo ... = field.Method; Type ... = TypeOf(TKey); // Create item, add item to diction, add fields to item's List // The item has the ThenBy method, which just adds another field to the List } I'm not sure if there is a way to store the entire field object in a way that would allow it be returned later (it would be impossible to cast, since it is a generic type) Is there a way I could adapt the sample code, or come up with entirely new code, in order to sort using strongly typed field names after they have been stored in some container and retrieved (losing any generic type casting)

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  • In C/C++ mode in Emacs, change face of code in #if 0...#endif block to comment face

    - by pogopop77
    I'm trying to add functionality found in some other code editors to my Emacs configuration, whereby C/C++ code within #if 0...#endif blocks is automatically set to the comment face/font. Based on my testing, cpp-highlight-mode does something like what I want, but requires user action. It seems like tying into the font-lock functionality is the correct option to make the behavior automatic. I have successfully followed examples in the GNU documentation to change the face of single-line regular expressions. For example: (add-hook 'c-mode-common-hook (lambda () (font-lock-add-keywords nil '(("\\<\\(FIXME\\|TODO\\|HACK\\|fixme\\|todo\\|hack\\)" 1 font-lock-warning-face t))))) works fine to highlight debug related keywords anywhere in a file. However, I am having problems matching #if 0...#endif as a multiline regular expression. I found some useful information in this post (How to compose region like ""), that suggested that Emacs must be told specifically to allow for multiline matches. But this code: (add-hook 'c-mode-common-hook (lambda () '(progn (setq font-lock-multiline t) (font-lock-add-keywords nil '(("#if 0\\(.\\|\n\\)*?#endif" 1 font-lock-comment-face t)))))) still does not work for me. Perhaps my regular expression is wrong (though it appears to work using M-x re-builder), I've messed up my syntax, or I'm following the wrong approach entirely. I'm using Aquamacs 2.1 (which is based on GNU Emacs 23.2.50.1) on OS X 10.6.5, if that makes a difference. Any assistance would be appreciated!

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  • Recursive Iterators

    - by soandos
    I am having some trouble making an iterator that can traverse the following type of data structure. I have a class called Expression, which has one data member, a List<object>. This list can have any number of children, and some of those children might be other Expression objects. I want to traverse this structure, and print out every non-list object (but I do want to print out the elements of the list of course), but before entering a list, I want to return "begin nest" and after I just exited a list, I want to return "end nest". I was able to do this if I ignored the class wherever possible, and just had List<object> objects with List<object> items if I wanted a subExpression, but I would rather do away with this, and instead have an Expressions as the sublists (it would make it easier to do operations on the object. I am aware that I could use extension methods on the List<object> but it would not be appropriate (who wants an Evaluate method on their list that takes no arguments?). The code that I used to generate the origonal iterator (that works) is: public IEnumerator GetEnumerator(){ return theIterator(expr).GetEnumerator(); } private IEnumerable theIterator(object root) { if ((root is List<object>)){ yield return " begin nest "; foreach (var item in (List<object>)root){ foreach (var item2 in theIterator(item)){ yield return item2; } } yield return " end nest "; } else yield return root; } A type swap of List<object> for expression did not work, and lead to a stackOverflow error. How should the iterator be implemented? Update: Here is the swapped code: public IEnumerator GetEnumerator() { return this.GetEnumerator(); } private IEnumerable theIterator(object root) { if ((root is Expression)) { yield return " begin nest "; foreach (var item in (Expression)root) { foreach (var item2 in theIterator(item)) yield return item2; } yield return " end nest "; } else yield return root; }

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  • Cost of logic in a query

    - by FrustratedWithFormsDesigner
    I have a query that looks something like this: select xmlelement("rootNode", (case when XH.ID is not null then xmlelement("xhID", XH.ID) else xmlelement("xhID", xmlattributes('true' AS "xsi:nil"), XH.ID) end), (case when XH.SER_NUM is not null then xmlelement("serialNumber", XH.SER_NUM) else xmlelement("serialNumber", xmlattributes('true' AS "xsi:nil"), XH.SER_NUM) end), /*repeat this pattern for many more columns from the same table...*/ FROM XH WHERE XH.ID = 'SOMETHINGOROTHER' It's ugly and I don't like it, and it is also the slowest executing query (there are others of similar form, but much smaller and they aren't causing any major problems - yet). Maintenance is relatively easy as this is mostly a generated query, but my concern now is for performance. I am wondering how much of an overhead there is for all of these case expressions. To see if there was any difference, I wrote another version of this query as: select xmlelement("rootNode", xmlforest(XH.ID, XH.SER_NUM,... (I know that this query does not produce exactly the same, thing, my plan was to move the logic to PL/SQL or XSL) I tried to get execution plans for both versions, but they are the same. I'm guessing that the logic does not get factored into the execution plan. My gut tells me the second version should execute faster, but I'd like some way to prove that (other than writing a PL/SQL test function with timing statements before and after the query and running that code over and over again to get a test sample). Is it possible to get a good idea of how much the case-when will cost? Also, I could write the case-when using the decode function instead. Would that perform better (than case-statements)?

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  • User will input some filter criteria -- how can I turn it into a regular expression for String.match

    - by envinyater
    I have a program where the user will enter a string such as PropertyA = "abc_*" and I need to have the asterisk match any character. In my code, I'm grabbing the property value and replacing PropertyA with the actual value. For instance, it could be abc_123. I also pull out the equality symbol into a variable. It should be able to cover this type of criteria PropertyB = 'cba' PropertyC != '*-this' valueFromHeader is the lefthand side and value is the righthand side. if (equality.equals("=")) { result = valueFromHeader.matches(value); } else if (equality.equals("!=")) { result = !valueFromHeader.matches(value); } EDIT: The existing code had this type of replacement for regular expressions final String ESC = "\\$1"; final String NON_ALPHA = "([^A-Za-z0-9@])"; final String WILD = "*"; final String WILD_RE_TEMP = "@"; final String WILD_RE = ".*"; value = value.replace(WILD, WILD_RE_TEMP); value = value.replaceAll(NON_ALPHA,ESC); value = value.replace(WILD_RE_TEMP, WILD_RE); It doesn't like the underscore here... abcSite_123 != abcSite_123 (evaluates to true) abcSite_123$1.matches("abcSite$1123") It doesn't like the underscore...

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  • GridView ObjectDataSource LINQ Paging and Sorting using multiple table query.

    - by user367426
    I am trying to create a pageing and sorting object data source that before execution returns all results, then sorts on these results before filtering and then using the take and skip methods with the aim of retrieving just a subset of results from the database (saving on database traffic). this is based on the following article: http://www.singingeels.com/Blogs/Nullable/2008/03/26/Dynamic_LINQ_OrderBy_using_String_Names.aspx Now I have managed to get this working even creating lambda expressions to reflect the sort expression returned from the grid even finding out the data type to sort for DateTime and Decimal. public static string GetReturnType<TInput>(string value) { var param = Expression.Parameter(typeof(TInput), "o"); Expression a = Expression.Property(param, "DisplayPriceType"); Expression b = Expression.Property(a, "Name"); Expression converted = Expression.Convert(Expression.Property(param, value), typeof(object)); Expression<Func<TInput, object>> mySortExpression = Expression.Lambda<Func<TInput, object>>(converted, param); UnaryExpression member = (UnaryExpression)mySortExpression.Body; return member.Operand.Type.FullName; } Now the problem I have is that many of the Queries return joined tables and I would like to sort on fields from the other tables. So when executing a query you can create a function that will assign the properties from other tables to properties created in the partial class. public static Account InitAccount(Account account) { account.CurrencyName = account.Currency.Name; account.PriceTypeName = account.DisplayPriceType.Name; return account; } So my question is, is there a way to assign the value from the joined table to the property of the current table partial class? i have tried using. from a in dc.Accounts where a.CompanyID == companyID && a.Archived == null select new { PriceTypeName = a.DisplayPriceType.Name}) but this seems to mess up my SortExpression. Any help on this would be much appreciated, I do understand that this is complex stuff.

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  • Match Anything Except a Sub-pattern

    - by Tim Lytle
    I'd like to accomplish what this (invalid I believe) regular expression tries to do: <p><a>([^(<\/a>)]+?)<\/a></p>uniquestring Essentially match anything except a closing anchor tag. Simple non-greedy doesn't help here because `uniquestring' may very well be after another distant closing anchor tag: <p><a>text I don't <tag>want</tag> to match</a></p>random data<p><a>text I do <tag>want to</tag> match</a></p>uniquestring more matches <p><a>of <tag>text I do</tag> want to match</a></p>uniquestring So I have more tag in between the anchor tags. And I'm using the presence of uniquestring to determine if I want to match the data. So a simple non-greedy ends up matching everything from the start of the data I don't want to the end of the data I do want. I know I'm edging close to the problems regular expressions (or at least my knowledge of them) aren't good at solving. I could just through the data at an HTML/XML parser, but it is just one simple(ish) search. Is there some easy way to do this that I'm just missing?

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