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  • Is there a modern free D?VCS that can ignore mainframe sequence numbers?

    - by Brent.Longborough
    I'm looking at migrating a large suite of IBM Assembler Language programs, from a vcs based on "filenames include version numbers", to a modern vcs which will give me, among other things, the ability to branch and merge. These files have 80-column records, the last 8 columns being an almost-meaningless sequence number. For a number of reasons which I don't really want to waste space by going into, I need the vcs to ignore (but hopefully preserve in some well-defined manner) the sequence number columns, and to diff and patch based only on the contents of the first 72 columns. Any ideas? Just to clarify "ignore but preserve": I accept it's a bit vague, as I haven't fully collected my ideas yet. It would be something along the lines of this: "When merging/patching, if one side has sequence numbers, output them; if more-than-one side has sequence numbers, use those present in file (1|2|3)" Why do I want to preserve sequence numbers? First, they really are sequence numbers. Second, I want to reintegrate this stuff back onto the mainframe, where sequence numbers can be terribly significant. (Those of you who know what "SMP/E" means will understand. Those who don't, be happy, but tremble...) I've just realised I hadn't accepted an answer. Difficult choice, but @Noldorin comes closest to where I have to go.

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  • How to use IsKeyboardFocusWithin and IsSelected together?

    - by jpsstavares
    I have a style defined for my ListBoxItems with a trigger to set a background color when IsSelected is True: <Style x:Key="StepItemStyle" TargetType="{x:Type ListBoxItem}"> <Setter Property="SnapsToDevicePixels" Value="true"/> <Setter Property="OverridesDefaultStyle" Value="true"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="ListBoxItem"> <Border Name="Border" Padding="0" SnapsToDevicePixels="true"> <ContentPresenter /> </Border> <ControlTemplate.Triggers> <Trigger Property="IsSelected" Value="True"> <Setter TargetName="Border" Property="Background" Value="#40a0f5ff"/> </Trigger> </ControlTemplate.Triggers> </ControlTemplate> </Setter.Value> </Setter> </Style> This style maintains the selected item even when the ListBox and ListBoxItem loses focus, which in my case is an absolute must. The problem is that I also want the ListBoxItem to be selected when one of its TextBox's child gets focused. To achieve this I add a trigger that sets IsSelected to true when IsKeyboardFocusWithin is true: <Trigger Property="IsKeyboardFocusWithin" Value="True"> <Setter Property="IsSelected" Value="True" /> </Trigger> When I add this trigger the Item is selected when the focus is on a child TextBox, but the first behaviour disappears. Now when I click outside the ListBox, the item is de-selected. How can I keep both behaviours?

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  • Executing javascript script after ajax-loaded a page - doesn't work

    - by Deukalion
    I'm trying to get a page with AJAX, but when I get that page and it includes Javascript code - it doesn't execute it. Why? Simple code in my ajax page: <script type="text/javascript"> alert("Hello"); </script> ...and it doesn't execute it. I'm trying to use Google Maps API and add markers with AJAX, so whenever I add one I execute a AJAX page that gets the new marker, stores it in a database and should add the marker "dynamically" to the map. But since I can't execute a single javascript function this way, what do I do? Is my functions that I've defined on the page beforehand protected or private? ** UPDATED WITH AJAX FUNCTION ** function ajaxExecute(id, link, query) { if (query != null) { query = query.replace("amp;", ""); } if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest(); } else { // code for IE6, IE5 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { if (id != null) { document.getElementById(id).innerHTML=xmlhttp.responseText; } } } if (query == null) { xmlhttp.open("GET",link,true); } else { if (query.substr(0, 1) != "?") { xmlhttp.open("GET",link+"?"+query,true); } else { xmlhttp.open("GET",link+query,true); } } xmlhttp.send(); }

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  • Is there a tool I can use to generate interfaces and wrappers for object mocking in c#

    - by fostandy
    Given a class like System.Timers.Timer, or ANY managed class (whether user defined, from the .net framework, or some 3rd party library) is there some program I can use to (a) generate an interface based on this class and (b) generate a wrapper for the given class? for example if I have a public class Foo { public object MyProperty { get { ... } set { ... } } public int SomeMethod(object a) { ... } } it will create an interface interface IFoo { object MyProperty { get; set; } int SomeMethod(object a) { ... } } and maybe even a wrapper class FooWrap { // something for relay constructor here ... Foo _me; public object MyProperty { get { return _me.MyProperty; } set { _me.MyProperty = value; } } public int SomeMethod(object a) { return _me.SomeMethod(); } } Obviously there's stuff I haven't thought about like events, generics etc. I want a DWIMNWIS-PSICHTO(-Plus-Stuff-I-Clearly-Haven't-Thought-Of). I'm aware resharper can be used to extract an interface but I've only been able to use this on my own classes. Aside: Wow, it is amazing how simply becoming accustomed to a previously 'unacceptable' idea eventually gives it legitimacy. A year ago the idea of having to create interfaces for all objects I want to mock and adopting an injection framework would have seemed like the height of madness. It turns out that while it's not quite death and taxes, it is sparta. I am aware of and have used typemock. It certainly is the work of elvish wizards. One day when $800 does not seem like quite so much money I intend to buy it.

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  • C#/LINQ: How to define generically a keySelector for a templated class before calling OrderBy

    - by PierrOz
    Hi Folks, I have the following class defined in C# class myClass<T,U> { public T PropertyOne { get; set; } public U PropertyTwo { get; set; } } I need to write a function that reorder a list of myClass objects and takes two other parameters which define how I do this reorder: does my reordering depend on PropertyOne or PropertyTwo and is it ascending or descending. Let's say this two parameters are boolean. With my current knowledge in LINQ, I would write: public IList<myClass<T,U>> ReOrder(IList<myClass<T,U>> myList, bool usePropertyOne, bool ascending) { if (usePropertyOne) { if (ascending) { return myList.OrderBy(o => o.PropertyOne).ToList(); } else { return myList.OrderByDescending(o => o.PropertyOne).ToList(); } } else { if (ascending) { return myList.OrderBy(o => o.PropertyTwo).ToList(); } else { return myList.OrderByDescending(o => o.PropertyTwo).ToList(); } } } What could be a more efficient/elegant way to do that ? How can I declare the Func,TResult keySelector object to reuse when I call either OrderBy or OrderByDescending? I'm interesting in the answer since in my real life, I can have more than two properties.

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  • Java many to many association map

    - by Raphael Jolivet
    Hi, I have to classes, ClassA and ClassB and a "many to many" AssociationClass. I want to use a structure to hold the associations between A and B such as I can know, for each instance of A or B, which are their counterparts. I thought of using a Hashmap, with pair keys: Hasmap<Pair<ClassA, ClassB>, AssociationClass> associations; This way, I can add and remove an association between two instances of ClassA and ClassB, and I can query a relation for two given instances. However, I miss the feature of getting all associations defined for a given instance of ClassA or ClassB. I could do it by brute force and loop over all keys of the map to search for associations between a given instance, but this is inefficient and not elegant. Do you know of any data structure / free library that enables this ? I don't want to reinvent the wheel. Thanks in advance for your help, Raphael NB: This is not a "database" question. These objects are pure POJO used for live computation, I don't need persistence stuff.

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  • Is it possible to execute a function in Mongo that accepts any parameters?

    - by joshua.clayton
    I'm looking to write a function to do a custom query on a collection in Mongo. Problem is, I want to reuse that function. My thought was this (obviously contrived): var awesome = function(count) { return function() { return this.size == parseInt(count); }; } So then I could do something along the lines of: db.collection.find(awesome(5)); However, I get this error: error: { "$err" : "error on invocation of $where function: JS Error: ReferenceError: count is not defined nofile_b:1" } So, it looks like Mongo isn't honoring scope, but I'm really not sure why. Any insight would be appreciated. To go into more depth of what I'd like to do: A collection of documents has lat/lng values, and I want to find all documents within a concave or convex polygon. I have the function written but would ideally be able to reuse the function, so I want to pass in an array of points composing my polygon to the function I execute on Mongo's end. I've looked at Mongo's geospatial querying and it currently on supports circle and box queries - I need something more complex.

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  • Read attributes of MSBuild custom tasks via events in the Logger

    - by gt
    I am trying to write a MSBuild logger module which logs information when receiving TaskStarted events about the Task and its parameters. The build is run with the command: MSBuild.exe /logger:MyLogger.dll build.xml Within the build.xml is a sequence of tasks, most of which have been custom written to compile a (C++ or C#) solution, and are accessed with the following custom Task: <DoCompile Desc="Building MyProject 1" Param1="$(Param1Value)" /> <DoCompile Desc="Building MyProject 2" Param1="$(Param1Value)" /> <!-- etc --> The custom build task DoCompile is defined as: public class DoCompile : Microsoft.Build.Utilities.Task { [Required] public string Description { set { _description = value; } } // ... more code here ... } Whilst the build is running, as each task starts, the logger module receives IEventSource.TaskStarted events, subscribed to as follows: public class MyLogger : Microsoft.Build.Utilities.Logger { public override void Initialize(Microsoft.Build.Framework.IEventSource eventSource) { eventSource.TaskStarted += taskStarted; } private void taskStarted(object sender, Microsoft.Build.Framework.TaskStartedEventArgs e) { // write e.TaskName, attributes and e.Timestamp to log file } } The problem I have is that in the taskStarted() method above, I want to be able to access the attributes of the task for which the event was fired. I only have access to the logger code and cannot change either the build.xml or the custom build tasks. Can anyone suggest a way I can do this?

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  • Searching a column containing CSV data in a MySQL table for existence of input values

    - by Adarsh R
    Hi, I have a table say, ITEM, in MySQL that stores data as follows: ID FEATURES -------------------- 1 AB,CD,EF,XY 2 PQ,AC,A3,B3 3 AB,CDE 4 AB1,BC3 -------------------- As an input, I will get a CSV string, something like "AB,PQ". I want to get the records that contain AB or PQ. I realized that we've to write a MySQL function to achieve this. So, if we have this magical function MATCH_ANY defined in MySQL that does this, I would then simply execute an SQL as follows: select * from ITEM where MATCH_ANY(FEAURES, "AB,PQ") = 0 The above query would return the records 1, 2 and 3. But I'm running into all sorts of problems while implementing this function as I realized that MySQL doesn't support arrays and there's no simple way to split strings based on a delimiter. Remodeling the table is the last option for me as it involves lot of issues. I might also want to execute queries containing multiple MATCH_ANY functions such as: select * from ITEM where MATCH_ANY(FEATURES, "AB,PQ") = 0 and MATCH_ANY(FEATURES, "CDE") In the above case, we would get an intersection of records (1, 2, 3) and (3) which would be just 3. Any help is deeply appreciated. Thanks

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  • File Storage for Web Applications: Filesystem vs DB vs NoSQL engines

    - by El Yobo
    I have a web application that stores a lot of user generated files. Currently these are all stored on the server filesystem, which has several downsides for me. When we move "folders" (as defined by our application) we also have to move the files on disk (although this is more due to strange design decisions on the part of the original developers than a requirement of storing things on the filesystem). It's hard to write tests for file system actions; I have a mock filesystem class that logs actions like move, delete etc, without performing them, which more or less does the job, but I don't have 100% confidence in the tests. I will be adding some other jobs which need to access the files from other service to perform additional tasks (e.g. indexing in Solr, generating thumbnails, movie format conversion), so I need to get at the files remotely. Doing this over network shares seems dodgy... Dealing with permissions on the filesystem as sometimes given us problems in the past, although now that we've moved to a pure Linux environment this should be less of an issue. What are the downsides of storing files as BLOBs in MySQL? I guess that it would massively increase the database size and reduce the effectiveness of caches, but are there other problems? Do the same problems exist with NoSQL systems like Cassandra? Does anyone have any other suggestions that might be appropriate?

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  • Handle order dependence in loops

    - by Matt
    Hey all, I'm making a templating system where I instantiate each tag using a foreach loop. The issue is that some of the tags rely on each other so, I'm wondering how to get around that ordering from the looping. Here's an example: Class A { public $width; __construct() { $this->width = $B->width; // Undefined! Or atleast not set yet.. } } Class B { public $width; __construct() { $this->width = "500px"; } __tostring() { return "Hello World!"; } } Template.php $tags = array("A", "B"); foreach ($tags as $tag) { $TagObj[$tag] = new $tag(); } echo $TagObj['A']->width; // Nadamundo! EDIT: Ok just to clarify.. My main problem is that Class A relies on Class B, but class A is instantiated before class B, so therefore width has not yet been defined in class B. I am looking for a good way to make sure all the classes are loaded for everyone allowing the interdependencies to exist. For the future, please don't consider any syntax errors.. I just made up this example on the spot. Also assume that I have access to class B from class A after class B gets instantiated. I know this has applications elsewhere and I'm sure this has been solved before, if someone could enlighten me or point me in the right direction that'd be great! Thanks! Matt Mueler

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  • Get email address from OpenID provider (Janrain openid library)

    - by Moak
    When signing in to stackoverflow with google I get this message Stackoverflow.com is asking for some information from your Google Account [email protected] • Email address: [email protected] However on my site I can log in with openid but I can't ask for the email address. I get this message You are signing in to example.com with your Google Account [email protected] Also I'm finding it hard to know at what step I need to ask for it, here's some code where I think that step should be built into. /** * Authenticates the given OpenId identity. * Defined by Zend_Auth_Adapter_Interface. * * @throws Zend_Auth_Adapter_Exception If answering the authentication query is impossible * @return Zend_Auth_Result */ public function authenticate() { $id = $this->_id; $consumer = new Auth_OpenID_Consumer($this->_storage); if (!empty($id)) { $authRequest = $consumer->begin($id); if (is_null($authRequest)) { return new Zend_Auth_Result( Zend_Auth_Result::FAILURE, $id, array("Authentication failed", 'Unknown error')); } if (Auth_OpenID::isFailure($authRequest)) { return new Zend_Auth_Result( Zend_Auth_Result::FAILURE, $id, array("Authentication failed", "Could not redirect to server: " . $authRequest->message)); } $redirectUrl = $authRequest->redirectUrl($this->_root, $this->_returnTo); if (Auth_OpenID::isFailure($redirectUrl)) { return new Zend_Auth_Result( Zend_Auth_Result::FAILURE, $id, array("Authentication failed", $redirectUrl->message)); } Zend_OpenId::redirect($redirectUrl); } else { $response = $consumer->complete(Zend_OpenId::selfUrl()); switch($response->status) { case Auth_OpenID_CANCEL: case Auth_OpenID_FAILURE: return new Zend_Auth_Result( Zend_Auth_Result::FAILURE, null, array("Authentication failed. " . @$response->message)); break; case Auth_OpenID_SUCCESS: return $this->_constructSuccessfulResult($response); break; } } } It seems like such an obvious thing but I'm having a hard time googling and combing through the code just to find this. Thanks!

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  • Schema-less design guidelines for Google App Engine Datastore and other NoSQL DBs

    - by jamesaharvey
    Coming from a relational database background, as I'm sure many others are, I'm looking for some solid guidelines for setting up / designing my datastore on Google App Engine. Are there any good rules of thumb people have for setting up these kinds of schema-less data stores? I understand some of the basics such as denormalizing since you can't do joins, but I was wondering what other recommendations people had. The particular simple example I am working with concerns storing searches and their results. For example I have the following 2 models defined in my Google App Engine app using Python: class Search(db.Model): who = db.StringProperty() what = db.StringProperty() where = db.StringProperty() createDate = db.DateTimeProperty(auto_now_add=True) class SearchResult(db.Model): title = db.StringProperty() content = db.StringProperty() who = db.StringProperty() what = db.StringProperty() where = db.StringProperty() createDate = db.DateTimeProperty(auto_now_add=True) I'm duplicating a bunch of properties between the models for the sake of denormalization since I can't join Search and SearchResult together. Does this make sense? Or should I store a search ID in the SearchResult model and effectively 'join' the 2 models in code when I retrieve them from the datastore? Please keep in mind that this is a simple example. Both models will have a lot more properties and the way I'm approaching this right now, I would put any property I put in the Search model in the SearchResult model as well.

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  • .NET: How to know when serialization is completed?

    - by Ian Boyd
    When I construct my control (which inherits DataGrid), I add specific rows and columns. This works great at design time. Unfortunately, at runtime I add my rows and columns in the same constructor, but then the DataGrid is serialized (after the constructor runs) adding more rows and columns. After serialization is complete, I need to clear everything and re-initialize the rows and columns. Is there a protected method that I can override to know when the control is done serializing? Of course, I'd prefer to not have to do the work in the constructor, throw it away, and do it again after (potential) serialization. Is there a preferred event that is the equivalent of "set yourself up now", so that it is called once whether I'm serialized or not? The serialization i speak of comes from the InitializeComponent() method in the form's code-behind file. #region Windows Form Designer generated code /// <summary> /// Required method for Designer support - do not modify /// the contents of this method with the code editor. /// </summary> private void InitializeComponent() { ... } It would have been perfect if InitializeComponent was a virtual method defined by Control, then i could just override it and then perform my processing after i call base: protected override void InitializeComponent() { base.InitializeComponent(); InitializeMe(); } But it's not an ancestor method, it's declared only in the code-behind file. i notice that InitializeComponent calls SuspendLayout and ResumeLayout on various Controls. i thought it could override ResumeLayout, and perform my initialization then: public override void ResumeLayout() { base.ResumeLayout(); InitializeMe(); } But ResumeLayout is not virtual, so that's out. Anymore ideas? i can't be the first person to create a custom control.

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  • DataGrid Column names don't seem to be binding

    - by Jason
    Sort of a Flex newbie here so bear with me. I've got a DataGrid defined as follows: <mx:Script> ... private function getColumns(names:ArrayCollection):Array { var ret:Array = new Array(); for each (var name:String in names) { var column:DataGridColumn = new DataGridColumn(name); ret.push(column); } return ret; } </mx:Script> <mx:DataGrid id="grid" width="100%" height="100%" paddingTop="0" columns="{getColumns(_dataSetLoader.columnNames)}" horizontalScrollPolicy="auto" labelFunction="labelFunction" dataProvider="{_dataSetLoader.data}" /> ...where _dataSetLoader is an instance of an object that looks like: [Bindable] public class DataSetLoader extends EventDispatcher { ... private var _data:ArrayCollection = new ArrayCollection(); private var _columnNames:ArrayCollection = new ArrayCollection(); ... public function reset():void { _status = NOTLOADED; _data.removeAll(); _columnNames.removeAll(); } ... When reset() is called on the dataSetLoader instance, the DataGrid empties the data in the cells, as expected, but leaves the column names, even though reset() calls _columnNames.removeAll(). Shouldn't the change in the collection trigger a change in the DataGrid?

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  • Redirecting to a Facelet is not working when extending FaceletViewHandler

    - by Abel Morelos
    I'm overriding the handleRenderResponse method defined in com.sun.facelets.FaceletViewHandler: protected void handleRenderException(FacesContext context, Exception ex) I'm overriding this method so I can redirect the user to a custom error page (which contain the desired look and feel and other stuff). This is the way I'm trying to String errorPage = "/error.xhtml"; String contextPath = context.getExternalContext().getRequestContextPath(); String errorPagePath = contextPath+errorPage; context.getExternalContext().redirect(errorPagePath); The previous code is what I'm using to perform the redirect to this custom error page. Anyway, when I perform the redirect I'm prompted with a download dialog (this is with Internet Explorer, in Firefox the page does not display properly or as I would expect). I tried changing "/error.xhtml" to "/error.jsf" but in that case I get a 404 error. Somehow I think that the XHTML file is not being handled to the Facelets ViewHandler after the redirect, if I open the downloaded xhtml file I can see that the EL expressions were not resolved and the the ui tags were not handled. I don't have problems with other pages in my application, only when doing the redirect programatically. Important data from my web.xml: facelets.VIEW_MAPPINGS is set to *.xhtml javax.faces.DEFAULT_SUFFIX is set to .xhtml servlet-mapping for the "Faces Servlet" is ".jsf" and "/faces/"

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  • C++ Multiple inheritance with interfaces?

    - by umanga
    Greetings all, I come from Java background and I am having difficulty with multiple inheritance. I have an interface called IView which has init() method.I want to derive a new class called PlaneViewer implementing above interface and extend another class. (QWidget). My implementation is as: IViwer.h (only Header file , no CPP file) : #ifndef IVIEWER_H_ #define IVIEWER_H_ class IViewer { public: //IViewer(); ///virtual //~IViewer(); virtual void init()=0; }; #endif /* IVIEWER_H_ */ My derived class. PlaneViewer.h #ifndef PLANEVIEWER_H #define PLANEVIEWER_H #include <QtGui/QWidget> #include "ui_planeviewer.h" #include "IViewer.h" class PlaneViewer : public QWidget , public IViewer { Q_OBJECT public: PlaneViewer(QWidget *parent = 0); ~PlaneViewer(); void init(); //do I have to define here also ? private: Ui::PlaneViewerClass ui; }; #endif // PLANEVIEWER_H PlaneViewer.cpp #include "planeviewer.h" PlaneViewer::PlaneViewer(QWidget *parent) : QWidget(parent) { ui.setupUi(this); } PlaneViewer::~PlaneViewer() { } void PlaneViewer::init(){ } My questions are: Is it necessary to declare method init() in PlaneViewer interface also , because it is already defined in IView? 2.I cannot complie above code ,give error : PlaneViewer]+0x28): undefined reference to `typeinfo for IViewer' collect2: ld returned 1 exit status Do I have to have implementation for IView in CPP file?

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  • Zipping with padding in Haskell

    - by Travis Brown
    A couple of times I've found myself wanting a zip in Haskell that adds padding to the shorter list instead of truncating the longer one. This is easy enough to write. (Monoid works for me here, but you could also just pass in the elements that you want to use for padding.) zipPad :: (Monoid a, Monoid b) => [a] -> [b] -> [(a, b)] zipPad xs [] = zip xs (repeat mempty) zipPad [] ys = zip (repeat mempty) ys zipPad (x:xs) (y:ys) = (x, y) : zipPad xs ys This approach gets ugly when trying to define zipPad3. I typed up the following and then realized that of course it doesn't work: zipPad3 :: (Monoid a, Monoid b, Monoid c) => [a] -> [b] -> [c] -> [(a, b, c)] zipPad3 xs [] [] = zip3 xs (repeat mempty) (repeat mempty) zipPad3 [] ys [] = zip3 (repeat mempty) ys (repeat mempty) zipPad3 [] [] zs = zip3 (repeat mempty) (repeat mempty) zs zipPad3 xs ys [] = zip3 xs ys (repeat mempty) zipPad3 xs [] zs = zip3 xs (repeat mempty) zs zipPad3 [] ys zs = zip3 (repeat mempty) ys zs zipPad3 (x:xs) (y:ys) (z:zs) = (x, y, z) : zipPad3 xs ys zs At this point I cheated and just used length to pick the longest list and pad the others. Am I overlooking a more elegant way to do this, or is something like zipPad3 already defined somewhere?

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  • Setting processor affinity on CSC.exe launched by CoreCompile MSBuild Task

    - by Hardy
    I am wondering if there is simple way to ensure that when a c# project is compiled the CSC.exe launched inherits the parent processor affinity settings, or perhaps of a way where by i can supply this. I have been trying to accomplish this by launching a bat file from vs.net cmd prompt like start /affinity 01 custombuild.cmd and inside my custombuild.cmd i have @echo off msbuild Libraries.sln /t:rebuild /p:Configuration=Release;platform=x64 /m:1 :END The command line call to Csc.exe this generates looks like the following C:\Windows\Microsoft.NET\Framework\v4.0.30319\Csc.exe ... ignoring the rest for brevity. What i 'd like to see is the CSC.exe to inherit the processor affinity or a simple way to be able to override how csc.exe call is generated so i can make it into a start /affinity 01 C:\Windows\Microsoft.NET\Framework\v4.0.30319\Csc.exe ... ignoring the rest for brevity. I also noticed that CoreCompile target is defined in Microsoft.CSharp.targets, should i be considering overriding MSBuildToolsPath variable so i can sneak in my own version. This feels rather hacky. Any help would be much appreciated.

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  • Does Perl auto-vivify variables used as references in subroutine calls?

    - by FM
    I've declared 2010 to be the year of higher-order programming, so I'm learning Haskell. The introduction has a slick quick-sort demo, and I thought, "Hey, that's easy to do in Perl". It turned to be easier than I expected. Note that I don't have to worry about whether my partitions ($less and $more) are defined. Normally you can't use an undefined value as an array reference. use strict; use warnings; use List::MoreUtils qw(part); my @data = (5,6,7,4,2,9,10,9,5,1); my @sorted = qsort(@data); print "@sorted\n"; sub qsort { return unless @_; my $pivot = shift @_; my ($less, $more) = part { $_ < $pivot ? 0 : 1 } @_; # Works, even though $less and $more are sometimes undefined. return qsort(@$less), $pivot, qsort(@$more); } As best I can tell, Perl will auto-vivify a variable that you try to use as a reference -- but only if you are passing it to a subroutine. For example, my call to foo() works, but not the attempted print. use Data::Dumper qw(Dumper); sub foo { print "Running foo(@_)\n" } my ($x); print Dumper($x); # Fatal: Can't use an undefined value as an ARRAY reference. # print @$x, "\n"; # But this works. foo(@$x); # Auto-vivification: $x is now []. print Dumper($x); My questions: Am I understanding this behavior correctly? What is the explanation or reasoning behind why Perl does this? Is this behavior explained anywhere in the docs?

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  • How do I get rid of these warnings?

    - by Brian Postow
    This is really several questions, but anyway... I'm working with a big project in XCode, relatively recently ported from MetroWorks (Yes, really) and there's a bunch of warnings that I want to get rid of. Every so often an IMPORTANT warning comes up, but I never look at them because there's too many garbage ones. So, if I can either figure out how to get XCode to stop giving the warning, or actually fix the problem, that would be great. Here are the warnings: It claims that <map.h> is antiquated. However, when I replace it with <map> my files don't compile. Evidently, there's something in map.h that isn't in map... this decimal constant is unsigned only in ISO C90 This is a large number being compared to an unsigned long. I have even cast it, with no effect. enumeral mismatch in conditional expression: <anonymous enum> vs <anonymous enum> This appears to be from a ?: operator. Possibly that the then and else branches don't evaluate to the same type? Except that in at least one case, it's (matchVp == NULL ? noErr : dupFNErr) And since those are both of type OSErr, which is mac defined... I'm not sure what's up. It also seems to come up when I have other pairs of mac constants... multi-character character constant This one is obvious. The problem is that I actually NEED multi-character constants... -fwritable-strings not compatible with literal CF/NSString I unchecked the "Strings are Read-Only" box in both the project and target settings... and it seems to have had no effect...

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  • What happened to the .NET version definition with v4.0?

    - by Tom Tresansky
    I'm building a C# class library, and using the beta 2 of Visual Web Developer/Visual C# 2010. I'm trying to save information about what version of .NET the library was built under. In the past, I was able to use this: // What version of .net was it built under? #if NET_1_0 public const string NETFrameworkVersion = ".NET 1.0"; #elif NET_1_1 public const string NETFrameworkVersion = ".NET 1.1"; #elif NET_2_0 public const string NETFrameworkVersion = ".NET 2.0"; #elif NET_3_5 public const string NETFrameworkVersion = ".NET 3.5"; #else public const string NETFrameworkVersion = ".NET version unknown"; #endif So I figured I could just add: #elif NET_4_0 public const string NETFrameworkVersion = ".NET 4.0"; Now, in Project-Properties, my target Framework is ".NET Framework 4". If I check: Assembly.GetExecutingAssembly().ImageRuntimeVersion I can see my runtime version is v4.0.21006 (so I know I have .NET 4.0 installed on my CPU). I naturally expect to see that my NETFrameworkVersion variable holds ".NET 4.0". It does not. It holds ".NET version unknown". So my question is, why is NET_4_0 not defined? Did the naming convention change? Is there some simple other way to determine .NET framework build version in versions 3.5?

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  • asp:login form does not submit when you hit enter

    - by Ben Liyanage
    I am having an issues while using the <asp:login> tag. When a user clicks the "login" button, the form will process correctly. However, when the user hits the enter key, the form self submits and does not process the login, whether it was correct information or not. I am using a combination of MasterPages, and Umbraco. My aspx code looks like this: <%@ Master Language="C#" MasterPageFile="/masterpages/AccountCenter.master" CodeFile="~/masterpages/Login.master.cs" Inherits="LoginPage" AutoEventWireup="true" %> <asp:Content ContentPlaceHolderID="RunwayMasterContentPlaceHolder" runat="server"> <div class="loginBox"> <div class="AspNet-Login-TitlePanel">Account Center Login</div> <asp:label id="output" runat="server"></asp:label> <asp:GridView runat="server" id="GridResults" AutoGenerateColumns="true"></asp:GridView> <asp:Login destinationpageurl="~/dashboard.aspx" ID="Login1" OnLoggedIn="onLogin" runat="server" TitleText="" FailureText="The login/password combination you provided is invalid." DisplayRememberMe="false"></asp:Login> </div> </asp:Content> In the actual rendered page, I see this javascript on the form: <form method="post" action="/dashboard.aspx?" onsubmit="javascript:return WebForm_OnSubmit();" id="aspnetForm"> That javascript function is defined as: <script type="text/javascript"> //<![CDATA[ function WebForm_OnSubmit() { if (typeof(ValidatorOnSubmit) == "function" && ValidatorOnSubmit() == false) return false; return true; } //]]> </script> The javascript is always evaluating to True when it runs.

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  • Intellisense on custom types in Iron Python

    - by Anish Patel
    Hi everybody, I'm just starting to play around with IronPython and am having a hard time using it with custom types created in C#. I can get IronPython to load in assemblies from C# classes, but I'm struggling without the help of intellisense. If I have a class in C# as defined below, how can I make it so that IronPython will be able to see the methods/properties that are available in it? public class Person { public string Name { get; set; } public int Age{ get; set; } public double Weight{ get; set; } public double Height { get; set; } public double CalculateBMI() { return Weight/Math.Pow(Height, 2); } } In Iron python I'd instance a Person object as follows: newPerson = Person() newPerson.Name = 'John' newPerson.Age = 25 newPerson.Weight = 75 newPerson.Height = 1.70 newPerson.CalculateBMI() The thing that is annoying me is that I want to be able to say newPerson = Person() And then be able to see all the methods and properties associated with the person object whenever I type: newPerson. Anyone have any ideas if this can be done?

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  • How can I set up an editor to work with Git on Windows?

    - by Patrick McElhaney
    I'm trying out Git on Windows. I got to the point of trying "git commit" and I got this error: Terminal is dumb but no VISUAL nor EDITOR defined. Please supply the message using either -m or -F option. So I figured out I need to have an environment variable called EDITOR. No problem. I set it to point to Notepad. That worked, almost. The default commit message opens in Notepad. But Notepad doesn't support bare line feeds. I went out and got Notepad++. But I can't figure out how to get Notepad++ set up as the %EDITOR% in such a way that it works with Git as expected. I'm not married to Notepad++. At this point I couldn't care less what editor I use. I just want to be able to type my commit messages without using -m. So, for those of you using Git on Windows: What (free) tool do you use to edit your commit message, and what do you get when you type echo %EDITOR% at the command prompt?

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