Search Results

Search found 5819 results on 233 pages for 'compiler theory'.

Page 158/233 | < Previous Page | 154 155 156 157 158 159 160 161 162 163 164 165  | Next Page >

• Objective-C categories: Can I add a property for a method not in my category?

  - by Squeegy

  I want to use a category to make a method on the original class available as a property as well. Class A: @interface ClassA - (NSString*)foo; @end Class A category @interface ClassA (Properties) - (void)someCategoryMethod; @property (nonatomic, readonly) NSString *foo; @end Now when I do this, it seems to work, but it gives me warnings because I am not synthesizing the property in my category implementation. How do I tell the compiler everything is actually just fine since the original class synthesizes the property for me?

  Read the article

• CString error, 'CString': is not a member of 'ATL::CStringT<BaseType, StringTraits>'

  - by flavour404

  Hi, I am trying to do this: #include <atlstr.h> CHAR Filename; // [sp+26Ch] [bp-110h]@1 char v31; // [sp+36Ch] [bp-10h]@1 int v32; // [sp+378h] [bp-4h]@1 GetModuleFileNameA(0, &Filename, 0x100u); CString::CString(&v31, &Filename); But I am getting the compiler error C2039:'CString': is not a member of 'ATL::CStringT' This is a non MFC based dll, but according to the docs you should be able to use CString functionality with the include #include atlstr.h how do I make it work? Thanks

  Read the article

• How can I access IEnumerable<T> extension methods on my custom subclass of BindingList<T>?

  - by Dan

  I have a custom subclass of BindingList<T> that I want to execute a LINQ query over using the handy extension methods. For example: public int GetSum(MyList<T> list) { return list.Sum(x => x.Value); } But the compiler complains that it can't resolve Sum because it doesn't recognize list as an IEnumerable<T>, which it obviously is, because this works: public int GetSum(MyList<T> list) { return ((IEnumerable<T>)list).Sum(x => x.Value); } Anyone have a clever way I can avoid the ugly and unecessary cast?

  Read the article

• How to implement dynamic queries for MNesia?

  - by Kerem

  I'm trying to implement a function that generates dynamic queries for MNesia. For example, when function is called with these arguments; dyn_query(list, person, [name, age], ["jack", 21]) I want to query MNesia to list items whose name is "jack" and age is 21 in person table. I've tried to implement this by using qlc:q(ListComprehension) and qlc:string_to_handle("ListComprehension"). First failed because of compile errors, compiler didn't let me to use functions instead of ListComprehentions and variables instead of record names like "Item#Table.Member". Second failed, because erl_eval couldn't handle records and throwed exceptions like {undefined_record, person}. Which method should I use? How could i solve these problems? Or should I use a different method? Thanks.

  Read the article

• Should I use concrete Inheritance or not?

  - by Mez

  I have a project using Propel where I have three objects (potentially more in the future) Occasion Event extends Occasion Gig extends Occasion Occasion is an item that has the shared things, that will always be needed (Venue, start, end etc) With this - I want to be able to add in extra functionality, say for example, adding "Band" objects to the Gig object, or "Flyers" to an "Event" object. For this, I plan to create objects for these. However, without concrete inheritance, I have to have the foreign key point to the Occasion object - giving the (propel generated) functions for all of these extra bits to anything inherited from Occasion. I could, in theory do this without a foreign constraint, and add in functions to use the Peer or Query classes to get things related to the "Gig" or similar. Whereas with concrete inheritance, I would only have these functions in the things where they are. I think the decision here is whether I should Duck Type the objects (after all they are occasions) or whether I should just use the "Occasion" object as a "template" (only being used to search for things, like, all occasions at a venue) Thoughts? Comments?

  Read the article

• eclipse gcov plugin

  - by Taani

  I am using gcov plugin in Eclipse CDT + cygwin compiler & linker to find code coverage. I installed gcov plugin from http://svn.sourceforge.jp/svnroot/ginkgo/trunk/org.ginko.gcov.update/ location and follow the below link to get coverage of my .c file. I was able to create .gcno and .gcda files. But double clicking on those files, opens the files in eclipse editor. I could not find the gcov editor. Also I couldn't see any code coverage results in my .c file. What is the wrong with my procedure?

  Read the article

• Is it possible to use WIndows Speech Recognition Engine in a word pronounciation game?

  - by XBasic3000

  I use to create an application that uses the windows speech recognition engine or the SAPI. its like a game for pronounciation that it give you score when you pronounce it correctly. but when i started experiments with SAPI, it has poor recognition unless if you load a grammar on it (XML) its give best recognition result. but the problem now is closest pronounciation from the input text will be recognize. for example: Database - dedebase - correct. even if you mispronounce it. it gives you correct answers. without using the xml grammar when you say database it give you "in the base/the base/data base/etc..." please post your answer,suggestion,clarication. votes for best answer. is it posible or not? by the way i use delphi compiler on the projects....

  Read the article

• Haskell Syntax: Parse Error On Input

  - by NuNu

  As part of a mini-haskell compiler that I'm writing, I have a function named app. What I want this function to do is take in these arguments epp (App e1 e2). The first step would be to evaluate e1 recursively (epp e1) and check if the output would be an error. If not then evaluate e2 and then call another function eppVals to evaluate the outputs of the calls on e1 and e2 which I defined as v1 and v2 respectively. epp (App e1 e2) | epp e1 /= Error = eppVals v1 v2 | otherwise = Error where v1 = epp e1 v2 = epp e2 <- parse error on input `=' Logically I believe what I have written so far works but I'm getting a parse error on input = where I stated above. Any idea why? My second try epp :: Exp -> Error Val epp (App e1 e2) = (eppVals v1 v2) where v1 = (epp e1) v2 = (epp e2) But now throws Couldn't match expected type Val with actual type Error Val

  Read the article

• C# ASP.Net The type or namespace name 'iAnywhere' could not be found

  - by Louis Russell

  Morning all, I know that this sounds like a simple referencing problem from the title this is becoming a nightmare! I have a code class that uses the "iAnywhere.Data.AsaClient.dll". This Dll is referenced in the project and in the code class I have added this dll in the Using section. Everything seems fine at build with no errors at all but when I go to run the application it comes up with the following Compilation Error: Compiler Error Message: CS0246: The type or namespace name 'iAnywhere' could not be found (are you missing a using directive or an assembly reference?) The line that the Error points to this line in the class: using iAnywhere.Data.AsaClient; I have set the dll to copy local and it makes no difference, the Dll is installed on my PC so is in the GAC, I use this Dll with many other C# projects and have no problems. I have scoured Google looking for an answer and haven't found anything that points me to an answer to my problem. Any help would be brilliant!

  Read the article

• In Delphi 7, why can I assign a value to a const?

  - by Blorgbeard

  I copied some Delphi code from one project to another, and found that it doesn't compile in the new project, though it did in the old one. The code looks something like this: procedure TForm1.CalculateGP(..) const Price : money = 0; begin ... Price := 1.0; ... end; So in the new project, Delphi complains that "left side cannot be assigned to" - understandable! But this code compiles in the old project. So my question is, why? Is there a compiler switch to allow consts to be reassigned? How does that even work? I thought consts were replaced by their values at compile time?

  Read the article

• What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?

  - by Jakub Šturc

  There are three assembly version attributes. What are differences? Is it ok if I use AssemblyVersion and ignore the rest? MSDN says: AssemblyVersion: Specifies the version of the assembly being attributed. AssemblyFileVersion: Instructs a compiler to use a specific version number for the Win32 file version resource. The Win32 file version is not required to be the same as the assembly's version number. AssemblyInformationalVersion: Defines additional version information for an assembly manifest. This is follow up to What are the best practices for using Assembly Attributes?

  Read the article

• How to improve workflow for creating a Lua-based Wireshark dissector

  - by piyo

  I've finally created a Dissector for my UDP protocol in Lua for Wireshark, but the work flow is just horrendous. It consists of editing my custom Lua file in my editor, then double-clicking my example capture file to launch Wireshark to see the changes. If there was an error, Wireshark informs me via dialogs or a red line in the Tree analysis sub-pane. I then re-edit my custom Lua file and then close that Wireshark instance, then double-click my example capture file again. It's like compiling a C file and only seeing one compiler error at a time. Is there a better (faster) way of looking at my changes, without having to restart Wireshark all the time? At the time, I was using Wireshark 1.2.9 for Windows with Lua enabled.

  Read the article

• FIFO implementation

  - by Narek

  While implementing a FIFO I have used the following structure: struct Node { T info_; Node* link_; Node(T info, Node* link=0): info_(info), link_(link) {} }; I think this a well known trick for lots of STL containers (for example for List). Is this a good practice? What it means for compiler when you say that Node has a member with a type of it's pointer? Is this a kind of infinite loop? And finally, if this is a bad practice, how I could implement a better FIFO. EDIT: People, this is all about implemenation. I am enough familiar with STL library, and know a plenty of containers from several libraries. Just I want to discuss with people who can gave a good implementation or a good advice.

  Read the article

• Interview - Program on Computer

  - by Gilad Naor

  Spent some time searching, couldn't find exactly what I'm after. We like giving hands-on programming exercises as part of the interview process. The interviewee gets a laptop, with the editor and compiler of his choice. He or she then get a programming exercise and has about an hour to code it. Depending on the nature of the question, internet access is either allowed or forbidden. I'm looking for good general questions for a junior developer. I don't care what language they choose to program in. C++ is as good as Python or Scheme, as long as (s)he can program in it (this rules out "can you write a correct copy-constructor" style questions). I just want to see how they code, if their code is self-documenting, if they write tests, check edge-cases, etc. What kind of questions would you ask?

  Read the article

• How does real world login process happen in web application in Java?

  - by Nitesh Panchal

  Hello, I am very much confused regarding login process that happen in Java web application. I read many tutorials regarding jdbcRealm and JAAS. But, one thing that i don't understand is that why should i use them ? Can't i simply check directly against my database of users? and once they successfully login to the site, i store some variable in session as a flag. And probably check that session variable on all restricted pages (I mean keep a filter for restricted resources url pattern).If the flag doesn't exist simply redirect the user to login page. Is this approach correct?Does this approch sound correct? If yes, then why did all this JAAS and jdbcRealm came into existence? Secondly, I am trying to completely implement SAS(Software as service) in my web application, meaning everything is done through web services.If i use webservices, is it possible to use jdbcRealm? If not, then is it possible to use JAAS? If yes, then please show me some example which uses mySql as a database and then authenticates and authorizes. I even heard about Spring Security. But, i am confused about that too in the sense that how do i use webservice with Spring Security. Please help me. I am really very confused. I read sun's tutorials but they only keep talking about theories. For programmers to understand a simple concept, they show a 100 page theory first before they finally come to one example.

  Read the article

• Would this method work to scale out SQL queries?

  - by David

  I have a database containing a single huge table. At the moment a query can take anything from 10 to 20 minutes and I need that to go down to 10 seconds. I have spent months trying different products like GridSQL. GridSQL works fine, but is using its own parser which does not have all the needed features. I have also optimized my database in various ways without getting the speedup I need. I have a theory on how one could scale out queries, meaning that I utilize several nodes to run a single query in parallel. The idea is to take an incoming SQL query and simply run it exactly like it is on all the nodes. When the results are returned to a coordinator node, the same query is run on the union of the resultsets. I realize that an aggregate function like average need to be rewritten into a count and sum to the nodes and that the coordinator divides the sum of the sums with the sum of the counts to get the average. What kinds of problems could not easily be solved using this model. I believe one issue would be the count distinct function. Edit: I am getting so many nice suggestions, but none have addressed the method.

  Read the article

• Yet another Haskell vs. Scala question

  - by Travis Brown

  I've been using Haskell for several months, and I love it—it's gradually become my tool of choice for everything from one-off file renaming scripts to larger XML processing programs. I'm definitely still a beginner, but I'm starting to feel comfortable with the language and the basics of the theory behind it. I'm a lowly graduate student in the humanities, so I'm not under a lot of institutional or administrative pressure to use specific tools for my work. It would be convenient for me in many ways, however, to switch to Scala (or Clojure). Most of the NLP and machine learning libraries that I work with on a daily basis (and that I've written in the past) are Java-based, and the primary project I'm working for uses a Java application server. I've been mostly disappointed by my initial interactions with Scala. Many aspects of the syntax (partial application, for example) still feel clunky to me compared to Haskell, and I miss libraries like Parsec and HXT and QuickCheck. I'm familiar with the advantages of the JVM platform, so practical questions like this one don't really help me. What I'm looking for is a motivational argument for moving to Scala. What does it do (that Haskell doesn't) that's really cool? What makes it fun or challenging or life-changing? Why should I get excited about writing it?

  Read the article

• CoreFoundation Lite on Linux and Android

  - by celil

  I would like to use Apple's CoreFoundation library on linux and android. The source code is available here, but there is very little documentation on how to build it on Linux. As far as I could figure out, building is done through a script called BuildCFLite. I grepped for DEPLOYMENT_TARGET ./CFUtilities.c:#if DEPLOYMENT_TARGET_MACOSX || DEPLOYMENT_TARGET_EMBEDDED || DEPLOYMENT_TARGET_LINUX || DEPLOYMENT_TARGET_FREEBSD and Linux seems to be supported at first site by setting -DDEPLOYMENT_TARGET_LINUX, but some of the compiler flags in that script are not available on linux, so when I try to build I get an error. Does anybody have experience building the latest version of CoreFoundation for Linux? Also what are the dependencies for building CoreFoundation? Would it be feasible to use it in the Android NDK?

  Read the article

• Expression Tree : C#

  - by nettguy

  My understanding of expression tree is : Expression trees are in-memory representation of expression like arithmetic or boolean expression.The expressions are stored into the parsed tree.so we can easily transalate into any other language. Linq to SQL uses expression tree.Normally when our LINQ to SQL query compiler translates it to parsed expression trees.These are passed to Sql Server as T-SQL Statements.The Sql server executes the T-SQL query and sends down the result back.That is why when you execute LINQ to SQL you gets IQueryable<T> not IEnumetrable<T>.Because IQuerybale contains public IQueryable:IEnumerable { Type Element {get;} Expression Expression {get;} IQueryaleProvider Provider {get;} } Questions : Microsoft uses Expression trees to play with LINQ-to-Sql.What are the different ways can i use expression trees to boost my code. Apart from LINQ to SQL,Linq to amazon ,who used expression trees in their applications? Linq to Object return IEnumerable,Linq to SQL return IQueryable ,What does LINQ to XML return?

  Read the article

• Using C# and gppg, how would I construct an abstract syntax tree?

  - by Rupert

  Is there a way to do this almost out-of-the-box? I could go and write a big method that would use the collected tokens to figure out which leaves should be put in which branches and in the end populate a TreeNode object, but since gppg already handled everything by using supplied regular expressions, I was wondering if there's an easier way? Even if not, any pointers as to how best to approach the problem of creating an AST would be appreciated. Apologies if I said anything silly, I'm only just beginning to play the compiler game. :)

  Read the article

• how to compile f# on mono

  - by leon

  I am trying to compile this example in mono on ubuntu. However I get the error wingsit@wingsit-laptop:~/MyFS/kitty$ fsc.exe -o kitty.exe kittyAst.fs kittyParser.fs kittyLexer.fs main.fs Microsoft (R) F# 2.0 Compiler build 2.0.0.0 Copyright (c) Microsoft Corporation. All Rights Reserved. /home/wingsit/MyFS/kitty/kittyAst.fs(1,1): error FS0222: Files in libraries or multiple-file applications must begin with a namespace or module declaration, e.g. 'namespace SomeNamespace.SubNamespace' or 'module SomeNamespace.SomeModule' /home/wingsit/MyFS/kitty/kittyParser.fs(2,1): error FS0222: Files in libraries or multiple-file applications must begin with a namespace or module declaration, e.g. 'namespace SomeNamespace.SubNamespace' or 'module SomeNamespace.SomeModule' /home/wingsit/MyFS/kitty/kittyLexer.fsl(2,1): error FS0222: Files in libraries or multiple-file applications must begin with a namespace or module declaration, e.g. 'namespace SomeNamespace.SubNamespace' or 'module SomeNamespace.SomeModule' wingsit@wingsit-laptop:~/MyFS/kitty$ I am a newbie in F#. Is there something obvious I miss?

  Read the article

• Python script to calculate aded combinations from a dictionary

  - by dayde

  I am trying to write a script that will take a dictionary of items, each containing properties of values from 0 - 10, and add the various elements to select which combination of items achieve the desired totals. I also need the script to do this, using only items that have the same "slot" in common. For example: item_list = { 'item_1': {'slot': 'top', 'prop_a': 2, 'prop_b': 0, 'prop_c': 2, 'prop_d': 1 }, 'item_2': {'slot': 'top', 'prop_a': 5, 'prop_b': 0, 'prop_c': 1, 'prop_d':-1 }, 'item_3': {'slot': 'top', 'prop_a': 2, 'prop_b': 5, 'prop_c': 2, 'prop_d':-2 }, 'item_4': {'slot': 'mid', 'prop_a': 5, 'prop_b': 5, 'prop_c':-5, 'prop_d': 0 }, 'item_5': {'slot': 'mid', 'prop_a':10, 'prop_b': 0, 'prop_c':-5, 'prop_d': 0 }, 'item_6': {'slot': 'mid', 'prop_a':-5, 'prop_b': 2, 'prop_c': 3, 'prop_d': 5 }, 'item_7': {'slot': 'bot', 'prop_a': 1, 'prop_b': 3, 'prop_c':-4, 'prop_d': 4 }, 'item_8': {'slot': 'bot', 'prop_a': 2, 'prop_b': 2, 'prop_c': 0, 'prop_d': 0 }, 'item_9': {'slot': 'bot', 'prop_a': 3, 'prop_b': 1, 'prop_c': 4, 'prop_d':-4 }, } The script would then need to select which combinations from the "item_list" dict that using 1 item per "slot" that would achieve a desired result when added. For example, if the desired result was: 'prop_a': 3, 'prop_b': 3, 'prop_c': 8, 'prop_d': 0, the script would select 'item_2', 'item_6', and 'item_9', along with any other combination that worked. 'item_2': {'slot': 'top', 'prop_a': 5, 'prop_b': 0, 'prop_c': 1, 'prop_d':-1 } 'item_6': {'slot': 'mid', 'prop_a':-5, 'prop_b': 2, 'prop_c': 3, 'prop_d': 5 } 'item_9': {'slot': 'bot', 'prop_a': 3, 'prop_b': 1, 'prop_c': 4, 'prop_d':-4 } 'total': 'prop_a': 3, 'prop_b': 3, 'prop_c': 8, 'prop_d': 0 Any ideas how to accomplish this? It does not need to be in python, or even a thorough script, but just an explanation on how to do this in theory would be enough for me. I have tried working out looping through every combination, but that seems to very quickly get our of hand and unmanageable. The actual script will need to do this for about 1,000 items using 20 different "slots", each with 8 properties. Thanks for the help!

  Read the article

• Matching .NET References to Namespaces

  - by maxp

  This seems confusing to me - im creating a class library, and adding all the necessary references for the source files contained in it. Now, off the bat, there were over 300 compiler errors complaining about missing namespaces. The library will now compile after i just added all of the System.* references, however this is obviously not the best way. I.e. if a classes needs using System.Web.Script;, there is no System.Web.Script reference, how would i find out which one of these references contained it? System.Web didnt.

  Read the article

• Difference of two 'uint'

  - by vanslly

  When you attempt to declare an unsigned variable in C#.NET with a value outside its value range it is flagged as a compiler error, but if you produce a negative value at runtime and assign it to that variable at runtime the value wraps. uint z = -1; // Will not compile uint a = 5; uint b = 6; uint c = a - b; // Will result in uint.MaxValue Is there a good reason why unsigned variables wrap in such a situation instead of throwing an exception? Thanks.

  Read the article

• std::map default value for build-in type

  - by Qifa Zhao

  Recently, I was confused by the std::map operator[] function. In the MSDN library, it says: "If the argument key value is not found, then it is inserted along with the default value of the data type." I tryed to search much more exactly explanation for this issue. For example here: std::map default value In this page, Michael Anderson said that "the default value is constructed by the default constructor(zero parameter constructor)". Now my quest comes to this:"what the default value for the build-in type?". Was it compiler related? Or is there a standard for this issue by the c++ stardard committee? I did a test on visual studio 2008 for the "int" type, and found the "int" type is construted with the value 0.

  Read the article

< Previous Page | 154 155 156 157 158 159 160 161 162 163 164 165  | Next Page >