Search Results

Search found 11536 results on 462 pages for 'whole foods market'.

Page 363/462 | < Previous Page | 359 360 361 362 363 364 365 366 367 368 369 370 | Next Page >

How to avoid chaotic ASP.NET web application deployment?

- by emzero

Ok, so here's the thing. I'm developing an existing (it started being an ASP classic app, so you can imagine :P) web application under ASP.NET 4.0 and SQLServer 2005. We are 4 developers using local instances of SQL Server 2005 Express, having the source-code and the Visual Studio database project This webapp has several "universes" (that's how we call it). Every universe has its own database (currently on the same server) but they all share the same schema (tables, sprocs, etc) and the same source/site code. So manually deploying is really annoying, because I have to deploy the source code and then run the sql scripts manually on each database. I know that manual deploying can cause problems, so I'm looking for a way of automating it. We've recently created a Visual Studio Database Project to manage the schema and generate the diff-schema scripts with different targets. I don't have idea how to put the pieces together I would like to: Have a way to make a "sync" deploy to a target server (thanksfully I have full RDC access to the servers so I can install things if required). With "sync" deploy I mean that I don't want to fully deploy the whole application, because it has lots of files and I just want to deploy those new or changed. Generate diff-sql update scripts for every database target and combine it to just 1 script. For this I should have some list of the databases names somewhere. Copy the site files and executing the generated sql script in an easy and automated way. I've read about MSBuild, MS WebDeploy, NAnt, etc. But I don't really know where to start and I really want to get rid of this manual deploy. If there is a better and easier way of doing it than what I enumerated, I'll be pleased to read your option. I know this is not a very specific question but I've googled a lot about it and it seems I cannot figure out how to do it. I've never used any automation tool to deploy. Any help will be really appreciated, Thank you all, Regards

Read the article
Database not completely updated in rails migration

- by Aatish Sai

I am new to Ruby on Rails. I have a migration called create user class CreateUsers < ActiveRecord::Migration def change create_table :users do |t| t.column :username, :string, :limit => 25, :default => "", :null => false t.column :hashed_password, :string, :limit => 40, :default => "", :null => false t.column :first_name, :string, :limit => 25, :default => "", :null => false t.column :last_name, :string, :limit => 40, :default => "", :null => false t.column :email, :string, :limit => 50, :default => "", :null => false t.column :display_name, :string, :limit => 25, :default => "", :null => false t.column :user_level, :integer, :limit => 3, :default => 0, :null => false end User.create(:username=>'test',:hashed_password=>'test',:first_name=>'test',:last_name=>'test',:email=>'[email protected]',:display_name=> 'test',:user_level=>9) end end When I run rake db:migrate the table is created with the columns as mentioned above but the test data are not there mysql>select * from users; Empty set (0.00 sec) EDIT I just dropped the whole database and restarted the migration and now it is showing the following error. rake aborted! An error has occurred, all later migrations canceled: Can't mass-assign protected attributes: username, hashed_password, first_name, last_name, email, display_name, user_level What am I doing wrong please help? Thank you.

Read the article
How to Create Element in XSLT When Copying Using Templates

- by John Dumont

Hello, I'm trying to create an element in an XML where the basic content is copied and modified. My XML is something like <root> <node> <child>value</child> <child2>value2</child2> </node> <node2>bla</node2> </root> The number of children of node may change as well as the children of root. The XSLT should copy the whole content, modify some values and add some new. The copying and modifying is no problem: <xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0"> <xsl:output method="xml" encoding="UTF-8"/> <xsl:template match="@*|node()"> <xsl:copy> <xsl:apply-templates select="@*|node()"/> </xsl:copy> </xsl:template> </xsl:stylesheet> (+ further templates for modifications). But how do I add a new element in this structure on some path, e.g. I want to add an element as the last element of the "node" node. The "node" element itself always exists.

Read the article
Merging two Regular Expressions to Truncate Words in Strings

- by Alix Axel

I'm trying to come up with the following function that truncates string to whole words (if possible, otherwise it should truncate to chars): function Text_Truncate($string, $limit, $more = '...') { $string = trim(html_entity_decode($string, ENT_QUOTES, 'UTF-8')); if (strlen(utf8_decode($string)) > $limit) { $string = preg_replace('~^(.{1,' . intval($limit) . '})(?:\s.*|$)~su', '$1', $string); if (strlen(utf8_decode($string)) > $limit) { $string = preg_replace('~^(.{' . intval($limit) . '}).*~su', '$1', $string); } $string .= $more; } return trim(htmlentities($string, ENT_QUOTES, 'UTF-8', true)); } Here are some tests: // Iñtërnâtiônàlizætiøn and then the quick brown fox... (49 + 3 chars) echo dyd_Text_Truncate('Iñtërnâtiônàlizætiøn and then the quick brown fox jumped overly the lazy dog and one day the lazy dog humped the poor fox down until she died.', 50, '...'); // Iñtërnâtiônàlizætiøn_and_then_the_quick_brown_fox_... (50 + 3 chars) echo dyd_Text_Truncate('Iñtërnâtiônàlizætiøn_and_then_the_quick_brown_fox_jumped_overly_the_lazy_dog and one day the lazy dog humped the poor fox down until she died.', 50, '...'); They both work as it is, however if I drop the second preg_replace() I get the following: Iñtërnâtiônàlizætiøn_and_then_the_quick_brown_fox_jumped_overly_the_lazy_dog and one day the lazy dog humped the poor fox down until she died.... I can't use substr() because it only works on byte level and I don't have access to mb_substr() ATM, I've made several attempts to join the second regex with the first one but without success. Please help S.M.S., I've been struggling with this for almost an hour. EDIT: I'm sorry, I've been awake for 40 hours and I shamelessly missed this: $string = preg_replace('~^(.{1,' . intval($limit) . '})(?:\s.*|$)?~su', '$1', $string); Still, if someone has a more optimized regex (or one that ignores the trailing space) please share: "Iñtërnâtiônàlizætiøn and then " "Iñtërnâtiônàlizætiøn_and_then_" EDIT 2: I still can't get rid of the trailing whitespace, can someone help me out?

Read the article
handling java exception

- by Noona

This questions is related to java exception, why are there some cases that when an exception thrown the program exits even though the exception was caught and there was no exit() statement? my code looks something like this void bindProxySocket(DefaultHttpClientConnection proxyConnection, String hostName, HttpParams params) { if (!proxyConnection.isOpen()) { Socket socket = null; try { socket = new Socket(hostName, 80); } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { proxyConnection.bind(socket, params); } catch(IOException e) { System.err.println ("couldn't bind socket"); e.printStackTrace(); } } } and then I call this method like this: bindProxySocket(proxyConn, hostName, params1); but, the program exits, although I want to handle the exception by doing something else, can it be because I didn't enclose the method call within a try catch clause? what happens if I catch the exception again even though it's already in the method? and what should I do if i want to clean resources only if an exception occurs and otherwise I want to continue with the program? I am guessing in this case I have to include the whole piece of code until I can clean the resources with in a try statement or can I do it in the handle exception statement? some of these questions are on this specific case, but I would like to get a thorough answer to all my questions for future reference. thanks

Read the article
Resize matrix in latex beamer

- by John Jiang

Hi I was wondering how to resize matrices in a beamer environment. Currently I am writing the following code: \begin{align*} \left( \begin{array}{ccccccc} 0 & 1 & & & & & \\ -1 & 0 & & & & & \\ & & 0 & 1 & & & \\ & & -1 & 0 & & & \\ & & & & \ddots & & \\ & & & & & 0 & 1 \\ & & & & & -1 & 0 \end{array} \right) \end{align*} and the matrix takes up almost a whole page. I would like it to be about half a page in height.

Read the article
TFS and Forms Authentication

- by George

I don't know squat about TFS, other than as a user who has performed simple check in/outs. I just installed it locally and would like to do joint development with a friend. I was having trouble making my TFS web site on port 8080 visible (the whole scoop is here if your interested) and I wonder if it could be related to the fact that TFS is probably using Windows Authentication to identify the user. Can TFS be set up to use forms authentication? We probably need to set up a VPN, though that's a learning curve too. To use TFS, do our machines have to belong to a domain? We're not admin types, though he is better than me, though I would be interested in any feedback or advice on which path is likely to pan out the best. I already got AxoSoft OneTime working in this type of an environment and it suits us well, but I am tempted at all the bells & whistles with TFS and the ability to tie tracked bug items to code changes. As far as finding a good way to share code, do sites like SourceForge allow one to keep code secure among members only?

Read the article
What makes merging in DVCS easy?

- by afriza

I read at Joel on Software: With distributed version control, the distributed part is actually not the most interesting part. The interesting part is that these systems think in terms of changes, not in terms of versions. and at HgInit: When we have to merge, Subversion tries to look at both revisions—my modified code, and your modified code—and it tries to guess how to smash them together in one big unholy mess. It usually fails, producing pages and pages of “merge conflicts” that aren’t really conflicts, simply places where Subversion failed to figure out what we did. By contrast, while we were working separately in Mercurial, Mercurial was busy keeping a series of changesets. And so, when we want to merge our code together, Mercurial actually has a whole lot more information: it knows what each of us changed and can reapply those changes, rather than just looking at the final product and trying to guess how to put it together. By looking at the SVN's repository folder, I have the impression that Subversion is maintaining each revisions as changeset. And from what I know, Hg is using both changeset and snapshot while Git is purely using snapshot to store the data. If my assumption is correct, then there must be other ways that make merging in DVCS easy. What are those?

Read the article
Print a string that contains a certain pattern in Java

- by jjpotter

I am trying to find a regular expression within a line of a .csv file, so I can eventually save all the matches to another file, and lose all the other junk. So a line in my file might look like: MachineName,User,IP,VariableData,Location The VariableData is what I want to match, and if there's a match, print the line. I am using a pattern for this because I only want 3 out of 10 of variations of VariableData, and out of those 3, they are numbered differently(example, "pc104, pccrt102, pccart65"). I am trying to do this using the Scanner Class and keeping it simple as possible so I can understand it. Here is where I was heading with this...(the pattern isn't complete, just have it like this for testing). import java.io.File; import java.util.Scanner; import java.util.regex.Pattern; public class pcv { public static void main(String[] args) { File myFile = new File("c:\\temp\\report.csv"); Pattern myPat = Pattern.compile("pc"); try{ Scanner myScan = new Scanner(myFile); while(myScan.hasNext()){ if(myScan.hasNext(myPat)){ System.out.println("Test"); } } }catch(Exception e){ } } } This code loops, im guessing the .hasNext() methods are resetting themselves. I've played around with the Matcher class a little bit, but only found a way to match the expression but not get the whole line. My other throught was maybe somehow count the line that contains the pattern, then go back and print the line that corresponds to the counts.

Read the article
SyntaxHighlighter and Line Break Tags

- by azamsharp

I am using the following syntax highligher: http://alexgorbatchev.com/wiki/SyntaxHighlighter For some reason when it encounter <br> it simply prints out <br> tags. I cannot replace the whole thing with System.Environment.NewLine since it will mess up the complete description. Here is my code: public static string GetDescription(string description) { string codeStartPattern = "<code>"; string codeEndPattern = "</code>"; Regex reg = new Regex(codeStartPattern); description = reg.Replace(description, ReplaceWithStartDiv); reg = new Regex(codeEndPattern); description = reg.Replace(description, ReplaceWithEndDiv); return description; } private static string ReplaceWithStartDiv(Match m) { return "<script type='syntaxhighlighter' class='brush: csharp'><![CDATA["; } private static string ReplaceWithEndDiv(Match m) { return "]]></script>"; } I guess I only need to replace <br> with System.Environment.Newline with the code that is between the <code> snippet here </code> Thanks!

Read the article
How to suggest changes as a recently-hired employee ?

- by ereOn

Hi, I was recently hired in a big company (thousands of people, to give an idea of the size). They said they hired me because of my rigor and because I was, despite my youngness (i'm 25), experienced as a C/C++ programer. Now that I'm in, I can see that the whole system is old and often uses obsolete technologies. There is no naming convention (files, functions, variables, ...), they don't use Version Control, don't use exceptions or polymorphism and it seems like almost everybody lost his passion (some of them are only 30 years old). I'd like to suggest somes changes but i don't want to be "the new guy that wants to change everything just because he doesn't want to fit in". I tried to "fit in", but actually, It takes me one week to do what I would do in one afternoon, just because of the poor tools we're forced to use. A lot my collegues never look at the new "things" and techniques that people use nowadays. It's like they just given up. The situation is really frustrating. Have you ever been in a similar situation and, if so, what advices would you give me ? Is there a subtle way of changing things without becoming the black sheep here ? Or should I just give up my passion and energy as well ? Thank you.

Read the article
MVC UI with Mock Controllers?

- by Jaimal Chohan

I'm working with Aspnet MVC 2 (R2) and at the same time playing about with the whole alt.net stack. One of this things I would like to be able todo is basically write my Views, and be able to interact with them without having to write the controller logic. E.g. I have a view that displays a list of orders and I can click on an order which redirects to another view where I can edit it, but I don't want to get into the nitty gritty of writing the code to actually get a list of orders, or update an existing ordes. I want to do so I can write UI tests in WaitN/AOT/Selenium without having to worry about whats happening underneath, and also It would help drive my controller logic on a need basis as opposed to guess work based of of the supplied screenshots How do you guys accomplish this atm? Can you provide links ot useful blog posts/tools/framework/articles with information on how to accomplish this p.s. I primarly use Rhino Mocks & NUnit but can happliy change to other tools if they support the above better.

Read the article
Problem with IE and Jquery qTip plugin

- by user272899

I am having problems with the Jquery qtip plugin. It works fine in Firefox (see here http://movieo.no-ip.org/ hover over the first image). But doesn't work in IE. This is the code: $('.moviebox').each(function() { $(this).qtip({ content: $(this).children('.info'), show: 'mouseover', hide: 'mouseout', style: { name: 'light' }, position: { corner: { target: 'rightbottom', tooltip: 'bottomleft' } } }); }); And the html  <div class="moviebox"> <a href="#"> <img src="http://1.bp.blogspot.com/_mySxtRcQIag/S6deHcoChaI/AAAAAAAAObc/Z1Xg3aB_wkU/s200/rising_sun.jpg" /> </a>  <div class="info"> <span>Rising Sun (2006)</span> <div class="description"><strong>Description:</strong><br /> test test test test test test test test test test test test test test test test</div> <img src="http://1.bp.blogspot.com/_mySxtRcQIag/S6deHcoChaI/AAAAAAAAObc/Z1Xg3aB_wkU/s200/rising_sun.jpg" /> <div class="cast"><strong>Cast:</strong><br /> Sean connery</div> <div class="rating"><strong>Rating:</strong><br />5stars</div> </div>  </div>  Why wouldn't that work in IE????? Beats me. Checkout movieo.no-ip.org for the whole source

Read the article
Natural language grammar and user-entered names

- by Owen Blacker

Some languages, particularly Slavic languages, change the endings of people's names according to the grammatical context. (For those of you who know grammar or studied languages that do this to words, such as German or Russian, and to help with search keywords, I'm talking about noun declension.) This is probably easiest with a set of examples (in Polish, to save the whole different-alphabet problem): Dorothy saw the cat — Dorota zobaczyla kota The cat saw Dorothy — Kot zobaczyl Dorote It is Dorothy’s cat — To jest kot Doroty I gave the cat to Dorothy — Dalam kota Dorotie I went for a walk with Dorothy — Poszlam na spacer z Dorota “Hello, Dorothy!” — “Witam, Doroto!” Now, if, in these examples, the name here were to be user-entered, that introduces a world of grammar nightmares. Importantly, if I went for Katie (Kasia), the examples are not directly comparable — 3 and 4 are both Kasi, rather than *Kasy and *Kasie — and male names will be wholly different again. I'm guessing someone has dealt with this situation before, but my Google-fu appears to be weak today. I can find a lot of links about natural-language processing, but I don'think that's quite what I want. To be clear: I'm only ever gonna have one user-entered name per user and I'm gonna need to decline them into known configurations — I'll have a localised text that will have placeholders something like {name nominative} and {name dative}, for the sake of argument. I really don't want to have to do lexical analysis of text to work stuff out, I'll only ever need to decline that one user-entered name. Anyone have any recommendations on how to do this, or do I need to start calling round localisation agencies ;o) Further reading (all on Wikipedia) for the interested: Declension Grammatical case Declension in Polish Declension in Russian Declension in Czech nouns and pronouns Disclaimer: I know this happens in many other languages; highlighting Slavic languages is merely because I have a project that is going to be localised into some Slavic languages.

Read the article
virtualenv macosX --no-site-package ignored

- by Tristram Gräbener

Hello, I'm having problems with macOSX and virtualenv. It seems to ignore --no-site-package. Using exactly the same commands with linux (archlinux) it works. It it macOSX 10.5 with python 2.5 curl -o virtualenv.py 'http://bitbucket.org/ianb/virtualenv/raw/tip/virtualenv.py Create a new environment python virtualenv.py --no-site-packages foo New python executable in foo/bin/python Installing setuptools...........................done. Activate it source foo/bin/activate Try to install something in it. Despite virtualenv it looks for the system-wide install easy_install cherrypy Searching for cherrypy Best match: CherryPy 3.1.2 Adding CherryPy 3.1.2 to easy-install.pth file Using /Library/Python/2.5/site-packages Processing dependencies for cherrypy Finished processing dependencies for cherrypy Yet it doesn't find the module (foo)guidage-multimodal:~ tristram$ python Python 2.5.1 (r251:54863, Feb 6 2009, 19:02:12) [GCC 4.0.1 (Apple Inc. build 5465)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import cherrypy Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: No module named cherrypy I tried PIP after looking at http://stackoverflow.com/questions/1382925/virtualenv-no-site-packages-and-pip-still-finding-global-packages However it fails installing psycopg2 (some problems with gcc). Also I would like to be able to have a setup.py (from distribute) that does the whole woork

Read the article
Yet another Python Windows CMD mklink problem ... can't get it to work!

- by Felix Dombek

OK I have just posted another question which outlined my program but the specific problem was different. Now, my program just stops working without any message whatsoever. I'd be grateful if someone could help me here. I want to create symlinks for each file in a directory structure, all in one large flat folder, and have the following code by now: # loop over directory structure: # for all items in current directory, # if item is directory, recurse into it; # else it's a file, then create a symlink for it def makelinks(folder, targetfolder, cmdprocess = None): if not cmdprocess: cmdprocess = subprocess.Popen("cmd", stdin = subprocess.PIPE, stdout = subprocess.PIPE, stderr = subprocess.PIPE) print(folder) for name in os.listdir(folder): fullname = os.path.join(folder, name) if os.path.isdir(fullname): makelinks(fullname, targetfolder, cmdprocess) else: makelink(fullname, targetfolder, cmdprocess) #for a given file, create one symlink in the target folder def makelink(fullname, targetfolder, cmdprocess): linkname = os.path.join(targetfolder, re.sub(r"[\/\\\:\*\?\"\<\>\|]", "-", fullname)) if not os.path.exists(linkname): try: os.remove(linkname) print("Invalid symlink removed:", linkname) except: pass if not os.path.exists(linkname): cmdprocess.stdin.write("mklink " + linkname + " " + fullname + "\r\n") So this is a top-down recursion where first the folder name is printed, then the subdirectories are processed. If I run this now over some folder, the whole thing just stops after 10 or so symbolic links. Here is the output: D:\Musik\neu D:\Musik\neu\# Electronic D:\Musik\neu\# Electronic\# tag & reencode D:\Musik\neu\# Electronic\# tag & reencode\ChillOutMix D:\Musik\neu\# Electronic\# tag & reencode\Unknown D&B D:\Musik\neu\# Electronic\# tag & reencode\Unknown D&B 2 The program still seems to run but no new output is generated. It created 9 symlinks for some files in the # tag & reencode and the first three files in the ChillOutMix folder. The cmd.exe Window is still open and empty, and shows in its title bar that it is currently processing the mklink command for the third file in ChillOutMix. I tried to insert a time.sleep(2) after each cmdprocess.stdin.write in case Python is just too fast for the cmd process, but it doesn't help. Does anyone know what the problem might be?

Read the article
What is session management in Java ?

- by Sarang

I have faced this question in my Interview as well. I do have many confusion with Session Scope & it management in java. In web.xml we do have the entry : <session-config> <session-timeout> 30 </session-timeout> </session-config> What does it indicate actually ? Is is scope of whole project ? Another point confusing me is how can we separate the session scope of multiple request in the same project? Means if I am logging in from a PC & at the same time I am logging in from another PC, does it differentiate it ? Also, another confusing thing is the browser difference. Why does the different Gmails possible to open in different browsers ? And Gmail can prevent a session from Login to Logout. How is it maintained with our personal web ?

Read the article
In Haskell, I want to read a file and then write to it. Do I need strictness annotation?

- by Steve

Hi, Still quite new to Haskell.. I want to read the contents of a file, do something with it possibly involving IO (using putStrLn for now) and then write new contents to the same file. I came up with: doit :: String -> IO () doit file = do contents <- withFile tagfile ReadMode $ \h -> hGetContents h putStrLn contents withFile tagfile WriteMode $ \h -> hPutStrLn h "new content" However this doesn't work due to laziness. The file contents are not printed. I found this post which explains it well. The solution proposed there is to include putStrLn within the withFile: doit :: String -> IO () doit file = do withFile tagfile ReadMode $ \h -> do contents <- hGetContents h putStrLn contents withFile tagfile WriteMode $ \h -> hPutStrLn h "new content" This works, but it's not what I want to do. The operation in I will eventually replace putStrLn might be long, I don't want to keep the file open the whole time. In general I just want to be able to get the file content out and then close it before working with that content. The solution I came up with is the following: doit :: String -> IO () doit file = do c <- newIORef "" withFile tagfile ReadMode $ \h -> do a <- hGetContents h writeIORef c $! a d <- readIORef c putStrLn d withFile tagfile WriteMode $ \h -> hPutStrLn h "Test" However, I find this long and a bit obfuscated. I don't think I should need an IORef just to get a value out, but I needed "place" to put the file contents. Also, it still didn't work without the strictness annotation $! for writeIORef. I guess IORefs are not strict by nature? Can anyone recommend a better, shorter way to do this while keeping my desired semantics? Thanks!

Read the article
How to architect Rails site that can be edited while running?

- by Chris Kimpton

Hi, I am writing a Rails app that "scrapes/navigates" some other websites and webservices for content. I am using Mechanize and Savon to do the heavylifting. But given the dynamic nature of the web, I'd like to make my calls to these editable by the admin users of the site - rather than requiring me to release a new version of the site. The actual scraping thread happens async to the website, using the daemons gem. My requirements are: Thinking that the scraping/webservice calling code is quite simple, the easiest route is to make the whole class editable by the admins. Keep a history of the scraping code - so that we can fairly easily revert if we introduce a problem. Initially use the code from the file system, but as soon as thats been edited and stored somewhere, to use that code instead. I am thinking my options are: Store the code in the db (with a history table for the old versions) Store the code in a private git repo somewhere and access that for the history/latest versions. I am thinking the git route might be easiest, given its raison d'etre is to track file history... But perhaps there is a gem/plugin that does all this for me, out of the box? Thanks in advance for any tips/advice. ~chris

Read the article
Mysterious extra hashtable entry

- by Harm De Weirdt

Good evening everyone, I'm back :) Let me explain my problem. I have a hashtable in wich I store the products a costumors buys (%orders). It uses the productcode as key and has a reference to an array with the other info as value. At the end of the program, I have to rewrite the inventory to the updated version (i.e. subtract the quantity of the bought items) This is how I do this: sub rewriteInventory{ open(FILE,'>inv.txt'); foreach $key(%inventory){ print FILE "$key\|$inventory{$key}[0]\|$inventory{$key}[1]\|$inventory{$key}[2]\n" } close(FILE); } where $inventory{$key}[x] is 0 - Title, 1 - price, 2 - quantity. The problem here is that when I look at inv.txt afterwards, I see things like this: CD-911|Lady Gaga - The Fame|15.99|21 ARRAY(0x145030c)||| BOOK-1453|The Da Vinci Code - Dan Brown|14.75|12 ARRAY(0x145bee4)||| Where do these "ARRAY(0x145030c)|||" entries come from? Or more important, how do I get rid of them? This is the last part of this school task, I had so much problems programming all this and this stupid little thing comes up now and I'm really fed up with this whole Perl thing. (this aside :p) I hope someone can help me :) Fuji

Read the article
Atomic Instructions and Variable Update visibility

- by dsimcha

On most common platforms (the most important being x86; I understand that some platforms have extremely difficult memory models that provide almost no guarantees useful for multithreading, but I don't care about rare counter-examples), is the following code safe? Thread 1: someVariable = doStuff(); atomicSet(stuffDoneFlag, 1); Thread 2: while(!atomicRead(stuffDoneFlag)) {} // Wait for stuffDoneFlag to be set. doMoreStuff(someVariable); Assuming standard, reasonable implementations of atomic ops: Is Thread 1's assignment to someVariable guaranteed to complete before atomicSet() is called? Is Thread 2 guaranteed to see the assignment to someVariable before calling doMoreStuff() provided it reads stuffDoneFlag atomically? Edits: The implementation of atomic ops I'm using contains the x86 LOCK instruction in each operation, if that helps. Assume stuffDoneFlag is properly cleared somehow. How isn't important. This is a very simplified example. I created it this way so that you wouldn't have to understand the whole context of the problem to answer it. I know it's not efficient.

Read the article
Which languages support *recursive* function literals / anonymous functions?

- by Hugh Allen

It seems quite a few mainstream languages support function literals these days. They are also called anonymous functions, but I don't care if they have a name. The important thing is that a function literal is an expression which yields a function which hasn't already been defined elsewhere, so for example in C, &printf doesn't count. EDIT to add: if you have a genuine function literal expression <exp>, you should be able to pass it to a function f(<exp>) or immediately apply it to an argument, ie. <exp>(5). I'm curious which languages let you write function literals which are recursive. Wikipedia's "anonymous recursion" article doesn't give any programming examples. Let's use the recursive factorial function as the example. Here are the ones I know: JavaScript / ECMAScript can do it with callee: function(n){if (n<2) {return 1;} else {return n * arguments.callee(n-1);}} it's easy in languages with letrec, eg Haskell (which calls it let): let fac x = if x<2 then 1 else fac (x-1) * x in fac and there are equivalents in Lisp and Scheme. Note that the binding of fac is local to the expression, so the whole expression is in fact an anonymous function. Are there any others?

Read the article
Merging: hg/git vs. svn

- by stmax

I often read that hg (and git and...) are better at merging than svn but I have never seen practical examples of where hg/git can merge something where svn fails (or where svn needs manual intervention). Could you post a few step-by-step lists of branch/modify/commit/...-operations that show where svn would fail while hg/git happily moves on? Practical, not highly exceptional cases please... Some background: we have a few dozen developers working on projects using svn, with each project (or group of similar projects) in its own repo. We know how to apply release- and feature-branches so we don't run into problems very often (i.e. we've been there, but we've learned to overcome joel's problems of "one programmer causing trauma to the whole team" or "needing six developers for two weeks to reintegrate a branch"). We have release-branches that are very stable and only used to apply bugfixes. We have trunks that should be stable enough to be able to create a release within one week. And we have feature-branches that single developers or groups of developers can work on. Yes, they are deleted after reintegration so they don't clutter up the repository. ;) So I'm still trying to find the advantages of hg/git over svn. I'd love to get some hands-on experience, but there aren't any bigger projects we could move to hg/git yet, so I'm stuck with playing with small artifical projects that only contain a few made up files. And I'm looking for a few cases where you can feel the impressive power of hg/git, since so far I have often read about them but failed to find them myself.

Read the article
Drawing to the canvas

- by Mattl

I'm writing an android application that draws directly to the canvas on the onDraw event of a View. I'm drawing something that involves drawing each pixel individually, for this I use something like: for (int x = 0; x < xMax; x++) { for (int y = 0; y < yMax; y++){ MyColour = CalculateMyPoint(x, y); canvas.drawPoint(x, y, MyColour); } } The problem here is that this takes a long time to paint as the CalculateMyPoint routine is quite an expensive method. Is there a more efficient way of painting to the canvas, for example should I draw to a bitmap and then paint the whole bitmap to the canvas on the onDraw event? Or maybe evaluate my colours and fill in an array that the onDraw method can use to paint the canvas? Users of my application will be able to change parameters that affect the drawing on the canvas. This is incredibly slow at the moment.

Read the article
client-server syncing methodology [theoretical]

- by Kenneth Ballenegger

I'm in the progress of building an web-app that syncs with an iOS client. I'm currently tackling trying to figure out how to go about about syncing. I've come up with following two directions: I've got a fairly simple server web-app with a list of items. They are ordered by date modified and as such syncing the order does not matter. One direction I'm considering is to let the client deal with syncing. I've already got an API that lets the client get the data, as well as do certain actions on it, such as update, add or remove single items. I was considering: 1) on each sync asking the server for all items modified since the last successful sync and updating the local records based on what's returned by the server, and 2) building a persistent queue of create / remove / update requests on the client, and keeping them until confirmation by the server. The risk with this approach is that I'm basically asking each side to send changes to the other side, hoping it works smoothly, but risking a diversion at some point. This would probably be more bandwidth-efficient, though. The other direction I was considering was a more traditional model. I would have a "sync" process in which the client would send its whole list to the server (or a subset since last modified sync), the server would update the data on the server (by fixing conflicts by keeping the last modified item, and keeping deleted items with a deleted = 1 field), and the server would return an updated list of items (since last successful sync) which the client would then replace its data with. Thoughts?

Read the article

< Previous Page | 359 360 361 362 363 364 365 366 367 368 369 370 | Next Page >