Search Results

Search found 28818 results on 1153 pages for 'main loop'.

Page 270/1153 | < Previous Page | 266 267 268 269 270 271 272 273 274 275 276 277  | Next Page >

  • Inherit static properties in subclass without redeclaration?

    - by David
    Hi, I'm having the same problem as this guy with the application I'm writing right now. The problem is that static properties are not being inherited in subclasses, and so if I use the static:: keyword in my main class, it sets the variable in my main class as well. It works if I redeclare the static variables in my subclass, but I expect to have a large number of static properties and subclasses and wish to avoid code duplication. The top-rated response on the page I linked has a link to a few "workarounds", but it seems to have 404'd. Can anyone lend me some help or perhaps point me in the direction of said workarounds?

    Read the article

  • python: can't terminate a thread hung in socket.recvfrom() call

    - by Dihlofos
    Hello, everyone I cannot get a way to terminate a thread that is hung in a socket.recvfrom() call. For example, ctrl+c that should trigger KeyboardInterrupt exception can't be caught. Here is a script I've used for testing: from socket import * from threading import Thread from sys import exit class TestThread(Thread): def __init__(self,host="localhost",port=9999): self.sock = socket(AF_INET,SOCK_DGRAM) self.sock.bind((host,port)) super(TestThread,self).__init__() def run(self): while True: try: recv_data,addr = self.sock.recvfrom(1024) except (KeyboardInterrupt, SystemExit): sys.exit() if __name__ == "__main__": server_thread = TestThread() server_thread.start() while True: pass The main thread (the one that executes infinite loop) exits. However the thread that I explicitly create, keeps hanging in recvfrom(). Please, help me resolve this.

    Read the article

  • wpf datagrid textbox + combobox

    - by Muhammad Adnan
    I have wpf datagrid with number of template columns. some of them have textbox in them in edit mode and some combobox. i need to give cut/copy/paste facility to user from main menu (ribbon) buttons of my application. when i select some text from textbox and press copy button from main menu. copy button becomes active control so i loose textbox as active control by which i could get selected text. (any solution for this) and second thing i wanted to ask... is there any event get fired when we select textbox's contents? or solution would be appreciated. Thanks in advance...

    Read the article

  • WCF Service with callbacks coming from background thread?

    - by Mark Struzinski
    Here is my situation. I have written a WCF service which calls into one of our vendor's code bases to perform operations, such as Login, Logout, etc. A requirement of this operation is that we have a background thread to receive events as a result of that action. For example, the Login action is sent on the main thread. Then, several events are received back from the vendor service as a result of the login. There can be 1, 2, or several events received. The background thread, which runs on a timer, receives these events and fires an event in the wcf service to notify that a new event has arrived. I have implemented the WCF service in Duplex mode, and planned to use callbacks to notify the UI that events have arrived. Here is my question: How do I send new events from the background thread to the thread which is executing the service? Right now, when I call OperationContext.Current.GetCallbackChannel<IMyCallback>(), the OperationContext is null. Is there a standard pattern to get around this? I am using PerSession as my SessionMode on the ServiceContract. UPDATE: I thought I'd make my exact scenario clearer by demonstrating how I'm receiving events from the vendor code. My library receives each event, determines what the event is, and fires off an event for that particular occurrence. I have another project which is a class library specifically for connecting to the vendor service. I'll post the entire implementation of the service to give a clearer picture: [ServiceBehavior( InstanceContextMode = InstanceContextMode.PerSession )] public class VendorServer:IVendorServer { private IVendorService _vendorService; // This is the reference to my class library public VendorServer() { _vendorServer = new VendorServer(); _vendorServer.AgentManager.AgentLoggedIn += AgentManager_AgentLoggedIn; // This is the eventhandler for the event which arrives from a background thread } public void Login(string userName, string password, string stationId) { _vendorService.Login(userName, password, stationId); // This is a direct call from the main thread to the vendor service to log in } private void AgentManager_AgentLoggedIn(object sender, EventArgs e) { var agentEvent = new AgentEvent { AgentEventType = AgentEventType.Login, EventArgs = e }; } } The AgentEvent object contains the callback as one of its properties, and I was thinking I'd perform the callback like this: agentEvent.Callback = OperationContext.Current.GetCallbackChannel<ICallback>(); How would I pass the OperationContext.Current instance from the main thread into the background thread?

    Read the article

  • Strange menu issue

    - by Ber53rker
    Just started out with Orchard and trying to just make pages and menus. I'm running into an issue where on my home page my menu shows: Home, Fruit, Vegetable, Carrot. I want it to show just Home, Fruit, Vegetable and when I click the respective item it adds the proper tabs. It DOES do it with Banana. ie: When I click Fruit, it shows Banana in the menu. But it always shows Carrot for some reason! I have the following setup. Navigation -Main Menu --Home --Fruit --Vegetable -Fruit Menu --Banana -Vegetable Menu --Carrot Widgits > Navigation > Main Menu, Fruit Menu, Vegetable Menu (Fruit and Vegetable Menus are in their own respective layers.) Path Examples: /Fruit, /Fruit/Banana, /Vegetable, /Vegetable/Carrot Thanks in advance.

    Read the article

  • Pure HTML + JavaScript client side templating

    - by Dev er dev
    I want to have achieve something similar to Java Tiles framework using only client side technologies (no server side includes). I would like to have one page, eg layout.html which will contain layout definition. Content placeholder in that page would be empty #content div tag. I would like to have different content injected on that page based on url. Something like layout.html?content=main or layout.html?content=edit will display page with content replaced with main.html or edit.html. The goal is to avoid duplicating code, even for layout, and to compose pages without server-side templating. What approach would you suggest? EDIT: I don't need a full templating library, just a way to compose a pages, similar for what tiles do.

    Read the article

  • newbie problems with codeigniter

    - by Patrick
    hi, i'm trying to learn codeigniter (following a book) but don't understand why the web page comes out empty. my controller is class Welcome extends Controller { function Welcome() { parent::Controller(); } function index() { $data['title'] = "Welcome to Claudia's Kids"; $data['navlist'] = $this->MCats->getCategoriesNav(); $data['mainf'] = $this->MProducts->getMainFeature(); $skip = $data['mainf']['id']; $data['sidef'] = $this->MProducts->getRandomProducts(3, $skip); $data['main'] = "home"; $this->load->vars($data); $this->load->view('template'); } the view is: <--doctype declaration etc etc.. --> </head> <body> <div id="wrapper"> <div id="header"> <?php $this->load->view('header');?> </div> <div id='nav'> <?php $this->load->view('navigation');?> </div> <div id="main"> <?php $this->load->view($main);?> </div> <div id="footer"> <?php $this->load->view('footer');?> </div> </div> </body> </html> Now I know the model is passing back the right variables, but the page appears completely blank. I would expect at least to see an error, or the basic html structure, but the page is just empty. Moreover, the controller doesn't work even if I modify it as follows: function index() { echo "hello."; } What am I doing wrong? Everything was working until I made some changes to the model - but even if I delete all those new changes, the page is still blank.. i'm really confused! thanks, P.

    Read the article

  • wxpython - Nested Notebooks

    - by madtowneast
    I have been trying to make my nested notebooks a little bit more appealing code wise. At the moment, I got this #!/usr/bin/env python import os import sys import datetime import numpy as np from readmonifile import MonitorFile from sortmonifile import sort import wx class NestedPanelOne(wx.Panel): #---------------------------------------------------------------------- # First notebook that creates the tab to select the component number #---------------------------------------------------------------------- def __init__(self, parent, label, data): wx.Panel.__init__(self, parent=parent, id=wx.ID_ANY) sizer = wx.BoxSizer(wx.VERTICAL) #Loop creating the tabs according to the component name nestedNotebook = wx.Notebook(self, wx.ID_ANY) for slabel in sorted(data[label].keys()): tab = NestedPanelTwo(nestedNotebook, label, slabel, data) nestedNotebook.AddPage(tab,slabel) sizer = wx.BoxSizer(wx.VERTICAL) sizer.Add(nestedNotebook, 1, wx.ALL|wx.EXPAND, 5) self.SetSizer(sizer) class NestedPanelTwo(wx.Panel): #------------------------------------------------------------------------------ # Second notebook that creates the tab to select the main monitoring variables #------------------------------------------------------------------------------ def __init__(self, parent, label, slabel, data): wx.Panel.__init__(self, parent=parent, id=wx.ID_ANY) sizer = wx.BoxSizer(wx.VERTICAL) nestedNotebook = wx.Notebook(self, wx.ID_ANY) for sslabel in sorted(data[label][slabel][data[label][slabel].keys()[0]].keys()): tab = NestedPanelThree(nestedNotebook, label, slabel, sslabel, data) nestedNotebook.AddPage(tab, sslabel) sizer.Add(nestedNotebook, 1, wx.ALL|wx.EXPAND, 5) self.SetSizer(sizer) class NestedPanelThree(wx.Panel): #------------------------------------------------------------------------------- # Third notebook that creates checkboxes to select the monitoring sub-variables #------------------------------------------------------------------------------- def __init__(self, parent, label, slabel, sslabel, data): wx.Panel.__init__(self, parent=parent, id=wx.ID_ANY) labels=[] chbox =[] chboxdict={} for ssslabel in sorted(data[label][slabel][data[label][slabel].keys()[0]][sslabel].keys()): labels.append(ssslabel) for item in list(set(labels)): cb = wx.CheckBox(self, -1, item) chbox.append(cb) chboxdict[item]=cb gridSizer = wx.GridSizer(np.shape(list(set(labels)))[0],3, 5, 5) gridSizer.AddMany(chbox) self.SetSizer(gridSizer) ######################################################################## class NestedNotebookDemo(wx.Notebook): #--------------------------------------------------------------------------------- # Main notebook creating tabs for the monitored components #--------------------------------------------------------------------------------- def __init__(self, parent, data): wx.Notebook.__init__(self, parent, id=wx.ID_ANY, style= wx.BK_DEFAULT ) for label in sorted(data.keys()): print label tab = NestedPanelOne(self,label, data) self.AddPage(tab, label) ######################################################################## class DemoFrame(wx.Frame): #---------------------------------------------------------------------- # Putting it all together #---------------------------------------------------------------------- def __init__(self,data): wx.Frame.__init__(self, None, wx.ID_ANY, "pDAQ monitoring plotting tool", size=(800,400) ) panel = wx.Panel(self) notebook = NestedNotebookDemo(panel, data) sizer = wx.BoxSizer(wx.VERTICAL) sizer.Add(notebook, 1, wx.ALL|wx.EXPAND, 5) panel.SetSizer(sizer) self.Layout() #Menu Bar to be added later ''' menubar = wx.MenuBar() file = wx.Menu() file.Append(1, '&Quit', 'Exit Tool') menubar.Append(file, '&File') self.SetMenuBar(menubar) self.Bind(wx.EVT_MENU, self.OnClose, id=1) ''' self.Show() #---------------------------------------------------------------------- if __name__ == "__main__": if len(sys.argv) == 1: raise SystemExit("Please specify a file to process") for f in sys.argv[1:]: data=sort.sorting(f) print data['stringHub'].keys() print data.keys() print data[data.keys()[0]].keys() print 'test' app = wx.PySimpleApp() frame = DemoFrame(data) app.MainLoop() print 'testend' and I would like to reduce this whole mess into something that only has three nested for loops, so something like for label in sorted(data.keys()): self.SubNoteBooks[label] = wx.Notebook(self.Notebook, wx.ID_ANY) self.Notebook.AddPage(self.SubNoteBooks[label], label) for slabel in sorted(data[label].keys()): self.SubNoteBooks[label][slabel] = wx.Notebook(self, wx.ID_ANY) self.SubNoteBooks[label].AddPage(self.SubNoteBooks[label][slabel], slabel) for sslabel in sorted(data[label][slabel][data[label][slabel].keys()[0]].keys()): self.SubNoteBooks[label][slabel][sslabel] = wx.Notebook(self.Notebook, wx.ID_ANY) self.Notebook.AddPage(self.SubNoteBooks[label][slabel][sslabel], sslabel) I have been trying to fiddle this around but the problem seems to be the line self.SubNoteBooks[label][slabel] = wx.Notebook(self, wx.ID_ANY) I get the error: Traceback (most recent call last): File "./reducelinenumbers.py", line 162, in <module> frame = DemoFrame(data) File "./reducelinenumbers.py", line 126, in __init__ self.SubNoteBooks[label][slabel] = wx.Notebook(self, wx.ID_ANY) TypeError: 'Notebook' object does not support item assignment I understand why notebook is being type raises a TypeError here. Is there a way around this? Thanks a bunch in advance.

    Read the article

  • How do I debug a difficult-to-reproduce crash with no useful call stack?

    - by David M
    I am encountering an odd crash in our software and I'm having a lot of trouble debugging it, and so I am seeking SO's advice on how to tackle it. The crash is an access violation reading a NULL pointer: First chance exception at $00CF0041. Exception class $C0000005 with message 'access violation at 0x00cf0041: read of address 0x00000000'. It only happens 'sometimes' - I haven't managed to figure out any rhyme or reason, yet, for when - and only in the main thread. When it occurs, the call stack contains one incorrect entry: For the main thread, which this is, it should show a large stack full of other items. At this point, all other threads are inactive (mostly sitting in WaitForSingleObject or a similar function.) I have only seen this crash occur in the main thread. It always has the same call stack of one entry, in the same method at the same address. This method may or may not be related - we do use the VCL in our application. My bet, though, is that something (possibly quite a while ago) is corrupting the stack, and the address where it's crashing is effectively random. Note it has been the same address across several builds, though - it's probably not truly random. Here is what I've tried: Trying to reproduce it reliably at a certain point. I have found nothing that reproduces it every time, and a couple of things that occasionally do, or do not, for no apparent reason. These are not 'narrow' enough actions to narrow it down to a particular section of code. It may be timing related, but at the point the IDE breaks in, other threads are usually doing nothing. I can't rule out a threading problem, but think it's unlikely. Building with extra debugging statements (extra debug info, extra asserts, etc.) After doing so, the crash never occurs. Building with Codeguard enabled. After doing so, the crash never occurs and Codeguard shows no errors. My questions: 1. How do I find what code caused the crash? How do I do the equivalent of walking back up the stack? 2. What general advice do you have for how to trace the cause of this crash? I am using Embarcadero RAD Studio 2010 (the project mostly contains C++ Builder code and small amounts of Delphi.)

    Read the article

  • Google Custom Search Engine not giving the expected search result.

    - by iecut
    Hi, I have been trying to create a new google custom search engine, but when I try some query,the search engine it is not giving me the expected search result.On some queries it is working fine, but on other queries, it says"no result". I tried adding the URL of the website that I wanted to search for, but there are certain pages and keywords that are not coming up in the search result when I try to search for the keyword of that page. I tired adding both the main page URL and the URL of the sub page that I want to search for, but nothing is working. There are some sub pages to the main URL that are coming in the search result.

    Read the article

  • Help calling class from a class above.

    - by wtzolt
    Hello, How to call from class oneThread: back to class fun:? As in, address a class written below. Is it possible? class oneThread(threading.Thread): def __init__(self): threading.Thread.__init__(self) self.start() def run(self): print "1" time.sleep(1) print "2" time.sleep(1) print "3" self.wTree.get_widget("entryResult").set_text("Done with One.") # How to call from here back to class fun, which of course is below...? class fun: wTree = None def __init__( self ): self.wTree = gtk.glade.XML( "main.glade" ) self.wTree.signal_autoconnect( {"on_buttonOne" : self.one} ) gtk.main() def one(self, widget): oneThread(); gtk.gdk.threads_init() do=fun()

    Read the article

  • jQuery class adding and removing with click and mouseleave

    - by danixd
    I just want to control a div by toggling a class on click, as well as removing it when the mouse leaves the div. I had it working with mouseout, but when I entered over a child element, the mouseOut triggered, so I know I need to use mouseleave. I am just unsure how incorporate telling jQuery the mouse has entered. Yes I am new to this! Here is my code: $(function(){ $('.main').click(function() { $(this).toggleClass('activated'); }); }); $(function(){ $('.main').mouseleave(function() { $(this).removeClass('activated'); }); });

    Read the article

  • Is it possible to nest folders in the Flash Builder bin-debug

    - by ThunderChunky_SF
    I'm trying to setup my bin-debug folder so that the structure looks like this: bin-debug assets img swf main.swf css style.css js swfobject.js index.html I've tried setting the project's output folder to: bin-debug/assets/swf which does get my main.swf where I want it, but then my other source folders get dumped into that swf folder as well. What I would really like is to tell Flash Builder to put my swf into a nested folder and to be able to specify where my build folders' output goes as well. Is this at all possible without resorting to ANT scripts?

    Read the article

  • C operating system createprozess

    - by Tyzak
    hello, i'm new at C Programming (i learned c++) i want to create a process with windows.h at first i just want to start my main programm that creates a process ( -- starts an other programm) that's my code, but it doesn't really work, i removed every unnessasery line of code but "void sleep(700)" (or "sleep (700)" for testing if the windows methods work, but i get an error, that "sleep" cant be found. #include <iostream> #include <windows.h> #include <string> using namespace std; void main() { //bool ret; //startupinfo stupinfo; //prozess_information pro2info; //Getstartupinfo (&stupinfo); //createprozess(null, "C:\\bsss10\\betriebssystemePRA1.exe", null, null, false, create_new_console, null, // null, &stupinfo, &pro2info); sleep (700); cout<< "hello"; } thanks in advance

    Read the article

  • Copying a java text file into a String.

    - by Deepak Konidena
    Hi, I run into the following errors when i try to store a large file into a string. Exception in thread "main" java.lang.OutOfMemoryError: Java heap space at java.util.Arrays.copyOf(Arrays.java:2882) at java.lang.AbstractStringBuilder.expandCapacity(AbstractStringBuilder.java:100) at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:515) at java.lang.StringBuffer.append(StringBuffer.java:306) at rdr2str.ReaderToString.main(ReaderToString.java:52) As is evident, i am running out of heap space. Basically my pgm looks like something like this. FileReader fr = new FileReader(<filepath>); sb = new StringBuffer(); char[] b = new char[BLKSIZ]; while ((n = fr.read(b)) > 0) sb.append(b, 0, n); fileString = sb.toString(); Can someone suggest me why i am running into heap space error? Thanks.

    Read the article

  • TCPClient in C# (Error).

    - by CSharp
    using System; using System.Text; using System.IO; using System.Net.Sockets; namespace ConsoleApp01 { class Program { public static void Main(string[] args) { TcpClient client = new TcpClient("python.org",80); NetworkStream ns = client.GetStream(); StreamWriter sw = new StreamWriter(ns); sw.Write("HEAD / HTTP/1.1\r\n" + "User-Agent: Test\r\n" + "Host: www.python.org\r\n" + "Connection: Close\r\n"); sw.Flush(); Console.ReadKey(true); } } } System.Net.Sockets.SocketException: Unable to make a connection because the target machine actively refused it at System.Net.Sockets.TcpClient..ctor at ConsoleApp01.Program.Main :line 12 Why do i get this error message?

    Read the article

  • Android: prevent user from coming back to login page after logging in

    - by user522559
    Hi all, I have a login page in my android app. I want to prevent the user after logging in to come back to the login page. Also, when the user reopens the app, if he has logged in before, I want to go directly to the main page without having to go to the login page. What the best way of doing that? One idea I thought of is to save the login parameters in a cookie, and then, when the app is reopens, if the cookie contains some login information, I inflate the main page, otherwise, I inflate the login page. Is this the best way of doing it? Thanks,

    Read the article

  • Android Template Application?

    - by stormin986
    I have built an application that I want to use as the foundation for a few other variants. The variants will come from assets / resource files and a unique AndroidManifest.xml. However, I want to be able to leave all the application code alone (modifying the package of all my classes, etc). I'm having a hard time figuring out how to do so. My first thought was to simply have my main application in its own package, and then specify the specific application package in the manifest. However, this gives me issues with the generated R.java class, since it is generated to be in the main application's package. Anyone have any thoughts on how to accomplish this? To have a code baseline, and the application variants happen in resources/assets and the manifest?

    Read the article

  • measuring performance - using real clicks vs "ab" command

    - by shanyu
    I have a web site in closed beta, developed in Django, runs with Mysql on Debian. In the last few days, the main page has been showing a slowdown. For every ten clicks, one or two receives extremely slow response (10 secs or more), others are as fast as they used to be. When I was searching for the problem, I ran into this issue that I couldn't grasp: top command shows that when I request the main page, mysql shoots up to 90% - 100% cpu usage. I get the page just as the cpu use gets back to normal. So, I thought, it is db. Then I called ab with parameters -n 1000 -c 5, I got decent performance, about 100 pages per second, just as it was before the slowdown. I would imagine a worse performance as 10-20% of requests take 10 secs to load. Is this conflict between ab and "real" clicks normal, or am I using ab in a wrong configuration?

    Read the article

  • CPU/GPU Monitering. (Tempature, current speed, etc) in C#

    - by Tommy
    Im looking for a way to moniter system statistics, here are my main points of interest: CPU Tempature CPU speed, (Cycles per second) CPU Load (Idle percent) GPU Tempature Some other points of interest: Memory useage Network Load (Traffic Up/Down) My ultimate goal is to write an application that can be used for easily running in the backround, and allow setting many events fr certain actions, for instance When processer temp gets to 56C -> Do _Blank_ etc. So this leaves me two main points. Is there a framework already out there for this sort of thing? If No to #1, How can i go about doing this?

    Read the article

  • XMLHttpRequest inside an oject: how to keep the refrence to "this"

    - by Julien
    I make some Ajax calls from inside a javascript object.: myObject.prototye = { ajax: function() { this.foo = 1; var req = new XMLHttpRequest(); req.open('GET', url, true); req.onreadystatechange = function (aEvt) { if (req.readyState == 4) { if(req.status == 200) { alert(this.foo); // reference to this is lost } } } }; Inside the onreadystatechange function, this does not refer to the main obecjt anymore, so I don't have access to this.foo. Ho can I keep the reference to the main object inside XMLHttpRequest events?

    Read the article

  • Latex label/ref for "fake" external figure

    - by Yannick Wurm
    Hello, some journals require each figure to be submitted in a separate document. However, they do want the figure legends to be listed in the main document. I was thus hoping to do something along these lines: \section{Figure Legends} \begin{description} \item[Figure \ref{fig:fireAntBiology}] \label{fig:fireAntBiology} bla bla ants \end{description} This would still permit to \ref the figure from the main text. However, it doesn't work (The \ref returns the number of section "Figure Legends"). The following correctly gives a different number to each "figure": \item[Figure \ref{fig:fireAntBiology}] \begin{figure} \caption{\label{fig:fireAntBiology}} \end{figure} bla bla ants However, it also places empty figure floats throughout the document. A solution should be straightforward. What am I missing? Any ideas? Thanks! yannick

    Read the article

  • Load array from plist in Documents Directory

    - by Florent
    Hi all ! I use to load plist which are in my main Bundle (Ressource folder) into an array using : NSString *path = [[[NSBundle mainBundle] resourcePath]stringByAppendingPathComponent:nomPlist ]; NSMutableArray *tmpQuestion = [[NSArray alloc] initWithContentsOfFile:path]; arrayQuestion = [ [NSArray alloc] initWithArray:tmpQuestion]; [tmpQuestion release]; since i decide to change the content of my plist and that main bundle is read only how can i make this array loading plist from the Documents directory of my app ? ? thanks to all

    Read the article

  • AJAX works fine in firefox, but malfunctions in Mozilla Prism 0.9

    - by Babiker
    I have the following ajax fucntion: function ajax(value, url, urlVarname, displayContainers_id){ if(value == ''){ document.getElementById(displayContainers_id).innerHTML=''; } /* THIS IS LINE 12*/ xmlhttp = new XMLHttpRequest(); xmlhttp.onreadystatechange=function() { if(xmlhttp.readyState == 4 && xmlhttp.status == 200){ document.getElementById(displayContainers_id).innerHTML=xmlhttp.responseText; } } xmlhttp.open('GET',url + '?varName=' + urlVarname + '&value=' + value, true); /* THIS IS LINE 25 */ xmlhttp.send(); } onmousedown="ajax(document.getElementById('searchParamater').value, 'http://192.168.0.7/controllers/search_controller.php', document.getElementById('searchBy').value, 'ajaxBucket')"> This whole thing works fine in firefox but when i use prism 0.9, it malfunctions and i get the following error in the errors console: Warning: assignment to undeclared variable xmlhttp Source File: http://192.168.0.7/javascript/main.js Line: 12 Error: uncaught exception: [Exception... "Not enough arguments [nsIXMLHttpRequest.send]" nsresult: "0x80570001 (NS_ERROR_XPC_NOT_ENOUGH_ARGS)" location: "JS frame :: http://192.168.0.7/javascript/main.js :: ajax :: line 25" data: no]

    Read the article

  • Using Constants in Perl

    - by David W.
    I am trying to define constants in Perl using the use Constant pragma: use Constant { FOO => "bar", BAR => "foo" }; I'm running into a bit of trouble, and hoping there's a standard way of handling it. First of all... I am defining a hook script for Subversion. To make things simple, I want to have a single file where the class (package) I'm using is in the same file as my actual script. Most of this package will have constants involved in it: print "This is my program"; package "MyClass"; use constant { FOO => "bar" }; sub new { yaddah, yaddah, yaddah. I would like my constant FOO to be accessible to my main program. I would like to do this without having to refer to it as MyClass::FOO. Normally, when the package is a separate file, I could do this in my main program: use MyClass qw(FOO); but, since my class and program are a single file, I can't do that. What would be the best way for my main program to be able to access my constants defined in my class? The second issue... I would like to use the constant values as hash keys: $myHash{FOO} = "bar"; The problem is that %myHash has the literal string FOO as the key and not the value of the constant. This causes problems when I do things like this: if (defined($myHash{FOO})) { print "Key " . FOO . " does exist!\n"; } I could force the context: if (defined("" . FOO . "")) { I could add parentheses: if (defined(FOO())) { Or, I could use a temporary variable: my $foo = FOO; if (defined($foo)) { None of these are really nice ways of handling this issue. So, what is the best way? Is there one way I'm missing? By the way, I don't want to use Readonly::Scalar because it is 1). slow, and 2). not part of the standard Perl package. I want to define my hook not to require additional Perl packages and to be as simple as possible to work.

    Read the article

< Previous Page | 266 267 268 269 270 271 272 273 274 275 276 277  | Next Page >