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  • how to use replace_regex_copy() from boost::algorithm library?

    - by Vincenzo
    This is my code: #include <string> #include <boost/algorithm/string/regex.hpp> string f(const string& s) { using namespace boost::algorithm; return replace_regex_copy(s, "\\w", "?"); } This is what compiler says: no matching function for call to ‘replace_regex_copy(const std::basic_string<char, std::char_traits<char>, std::allocator<char> >&, std::string, std::string) The link to the library: http://www.boost.org/doc/libs/1_43_0/doc/html/boost/algorithm/replace_regex_copy.html Could anyone please help? Thanks! ps. Boost library is in place, since other functions from it work fine.

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  • writing structs and classes to disk

    - by Phenom
    The following function writes a struct to a file. int btwrite(short rrn, BTPAGE *page_ptr) { long addr; addr = (long) rrn * (long) PAGESIZE + HEADERSIZE; lseek(btfd, addr, 0); return (write(btfd, page_ptr, PAGESIZE)); } The following is the struct. typedef struct { short keycount; /* number of keys in page */ int key[MAXKEYS]; /* the actual keys */ int value[MAXKEYS]; /* the actual values */ short child[MAXKEYS+1]; /* ptrs to rrns of descendants */ } BTPAGE; What would happen if I changed the struct to a class, would it still work the same? If I added class functions, would the size it takes up on disk increase?

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  • What is the smallest Windows header I can #include to define DWORD?

    - by j_random_hacker
    I have a small header file of my own which declares a couple of functions, one of which has a return type of DWORD. I'm reluctant to drag in windows.h just to get the official definition of this type since that file is huge, and my header will be used in a number of source modules that don't otherwise need it. Of course, in practice I know that DWORD is just unsigned int, but I'd prefer the more hygienic approach of including an official header file if possible. On this page it says that DWORD is defined in windef.h, but unfortunately including just this small file directly leads to compilation errors -- apparently it expects to be included by other headers. (Also, the fact that my file is a header file also means I can't just declare WIN32_LEAN_AND_MEAN, since the source file that #includes my file might need this to be left undefined.) Any ideas? I know it's not the end of the world -- I can just continue to #include <windows.h> -- but thought someone might have a better idea!

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  • Should I convert data arrays to objects in PHP in a CouchDB/Ajax app?

    - by karlthorwald
    I find myself converting between array and object all the time in PHP application that uses couchDB and Ajax. Of course I am also converting objects to JSON and back (for sometimes couchdb but mostly Ajax), but this is not so much disturbing my workflow. At the present I have php objects that are returned by the CouchDB modules I use and on the other hand I have the old habbit to return arrays like array("error"="not found","data"=$dataObj) from my functions. This leads to a mixed occurence of real php objects and nested arrays and I cast with (object) or (array) if necessary. The worst thing is that I know more or less by heart what a function returns, but not what type (array or object), so I often run into type errors. My plan is now to always cast arrays to objects before returning from a function. Of course this implies a lot of refactoring. Is this the right way to go? What about the conversion overhead? Other ideas or tips?

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  • Why does coffeescript generate classes like this?

    - by ryeguy
    Given the following coffeescript code: class Animal constructor: (@name) -> speak: (things) -> "My name is #{@name} and I like #{things}" This is generated: var Animal = (function() { function Animal(name) { this.name = name; } Animal.prototype.speak = function(things) { return "My name is " + this.name + " and I like " + things; }; return Animal; })(); But why isn't this more idiomatic code generated? var Animal = function Animal(name) { this.name = name; }; Animal.prototype.speak = function(things) { return "My name is " + this.name + " and I like " + things; }; I know that coffeescript wraps a lot of stuff in anonymous functions to control scope leak, but what could leak here?

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  • Function to set an auth_token

    - by john mossel
    In my form I have a hidden field: <input type="hidden" name="auth_token" value="<?php echo $auth_token; ?>"> This value is also stored in a session and a variable: $_SESSION['auth_token'] = hash('sha256', rand() . time() . $_SERVER['HTTP_USER_AGENT']); # TODO: put this in a function $auth_token = $_SESSION['auth_token']; When the form is submitted the two values are compared. It's a basic form token. Should this be made into two functions or just one when refactored? set_form_token() and get_form_token(), get_form_token() returning the session value, then I can compare it in my main code. What is the proper way of doing this?

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  • F# - Function with no arguments?

    - by Rubys
    When thinking in a functional mindset, given that functions are supposed to be pure, one can conclude any function with no arguments is basically just a value. However, reallity gets in the way, and with different inputs, I might not need a certain function, and if that function is computationally expensive, I'd like to not evaluate it if it's not needed. I found a workaround, using let func _ = ... and calling it with func 1 or whatever, but that feels very non-idiomatic and confusing to the reader. This boils down to one question: In F#, Is there a proper way to declare a function with zero arguments, without having it evaluated on declaration?

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  • Micro Controller Serial Data identification or classification

    - by Posiedon
    I have a x51 family micro controller (P89V51RD2). I'm going to send some data from computer using serial port. The data i'll be sending are Character 'S' Character 'R' and a 2 digit integer. Upon receiving the data, I will be calling separate functions. I used if(chr=='S') and elseif(chr=='R')for character data. The main problem lies with identifying the 2 digit number sent. Any other data other than the above three mentioned will be discarded. Any ideas for identifying two digit integer ??

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  • Is PThread a good choice for multi-platorm C/C++ multi-threading program?

    - by RogerV
    Been doing mostly Java and smattering of .NET for last five years and haven't written any significant C or C++ during that time. So have been away from that scene for a while. If I want to write a C or C++ program today that does some multi-threading and is source code portable across Windows, Mac OS X, and Linux/Unix - is PThread a good choice? The C or C++ code won't be doing any GUI, so won't need to worry with any of that. For the Windows platform, I don't want to bring a lot of Unix baggage, though, in terms of unix emulation runtime libraries. Would prefer a PThread API for Windows that is a thin-as-possible wrapper over existing Windows threading APIs. ADDENDUM EDIT: Am leaning toward going with boost:thread - I also want to be able to use C++ try/catch exception handling too. And even though my program will be rather minimal and not particularly OOPish, I like to encapsulate using class and namespace - as opposed to C disembodied functions.

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  • Creating a Drop-Down Menu with Javascript

    - by iceteea
    Question about logics here: What's the most elegant way to make the menu appear/disappear onmouseover/onmouseout? See the following JsBin: http://jsbin.com/owayeb/edit#source The Menu is hidden by default. If the user moves his cursor above the Link the showme() function gets called. When the user moves his cursor away the hideme() functions gets called. How would I get the Menu to persist while the user moves his mouse away from the Link to above the Menu? Or is this all the wrong school of thought?

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  • Getting imagename and make link from <img> with jQuery

    - by Bulan
    With jQuery, I want to make all images under a specific path on a site clickable and showing a big image using Fancybox, which is a lighbox variant plugin for jQuery. My small images are located under "images/products/small", the big ones under "images/products/big" and the imagename is always the same The page is showing the image with the following code: <img src="images/products/small/hat.jpg" alt="Nice hat"> What i want is some jQuery script that makes this into: <a href="images/products/big/hat.jpg" class="fancybox"><img src="images/products/small/hat.jpg" alt="Nice hat"></a> Maybe the part with setting class on the link tag can be skipped and just activate fancybox on the element directly with $(elm).fancybox(); I was looking around a bit and it looks like the jQuery functions "attr" and "wrap" might be useful, but with my currently limited jQuery skills I can't really connect the dots.

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  • returning values from function or method multiple times by only calling the class once

    - by Sokhrat Sikar
    I have a members.php file that shows my websites members. I echo members name by using foreach method. A method of Members class returns an array, then I use foreach loop in the members.php file to echo the members. I am trying to aovid writing php code in my members.php file. Is there a way to avoid using foreach inside members.php file? For example, is it possible to return value from a method couple of times? (by only calling the object once). Just like how we normally call the functions? This question doesn't make sense, but I am just trying to see if there is a away around this issue?

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  • wordpress: previous_post_link() / next_post_link() placeholder

    - by superUntitled
    I am having trouble with the previous_post_link() and next_post_link() functionality. When there is no previous post, the function previous_post_link() does not display a link, likewise for the next_post_link() and the last post. I would like to have a placeholder image so that the design stays consistent. Currently I have images of green arrows pointing left and right, I would like to place an image of a grey arrow if there are no more posts to go back to. Is there a way to use the next_post_link()/previous_post_link() functions but not have the link removed. I also wonder if there is a way for the links to cycle, so that if you come to the most recent post, the next post link would bring you back to the first post.

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  • More compact way to do this?

    - by Macha
    I have a couple of functions that loop around the surrounding cells of a cell. The grid is contained inside an array. In my code, I have checks to make sure it's not one of the edge cells, as checking an undefined cell causes an error. As such, I have code like this: if(x > 0) { var firstX = x - 1; } else { var firstX = x; } if(x < 199) { var lastX = x + 1; } else { var lastX = x; } if(y > 0) { var firstY = y - 1; } else { var firstY = y; } if(y < 199) { var lastY = y + 1; } else { var lastY = y; } A lot of lines of code to do very little. Is there a more elegant way to do this?

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  • Issues with Sinatra and Heroku

    - by Brian Michel
    So I've created and published a Sinatra app to Heroku without any issues. I've even tested it locally with rackup to make sure it functions fine. There are a series of API calls to various places after a zip code is consumed from the URL, but Heroku just wants to tell me there is an server error. I've added an error page that tries to give me more description, however, it tells me it can't perform a `count' for #, which I assume means hash. Here's the code that I thin it's trying to execute... if weather_doc.root.elements["weather"].children.count > 1 curr_temp = weather_doc.root.elements["weather/current_conditions/temp_f"].attributes["data"] else raise error(404, "Not A Valid Zip Code!") end If anyone wants to bang on it, it can be reached at, http://quiet-journey-14.heroku.com/ , but there's not much to be had.

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  • Doubt about a particular pattern of Javascript class definition

    - by fenderplayer
    Recently i saw the following code that creates a class in javascript: var Model.Foo = function(){ // private stuff var a, b; // public properties this.attr1 = ''; this.attr2 = ''; if(Model.Foo._init === 'undefined'){ Model.Foo.prototype = { func1 : function(){ //...}, func2 : function(){ //... }, //other prototype functions } } Model.Foo._init = true; } // Instantiate and use the class as follows: var foo = new Model.Foo(); foo.func1(); I guess the _init variable is used to make sure we don't define the prototypes again. Also, i feel the code is more readable since i am placing everything in a function block (so in oop-speak, all attributes and methods are in one place). Do you see any issues with the code above? Any pitfalls of using this pattern if i need to create lots of classes in a big project?

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  • How to convert server time to local time?

    - by Lost_in_code
    My php file is hosted in some other part of the world. The date() and time() functions returns the date/time on the server. How do I convert that date so that it's the same as my local date/time? The date on the server is 10 hours behind my local time. I could just hard code and substract this from the server time. But what is the proper way of going about this so that no value has to be hardcoded?

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  • MySQL LEFT JOIN issue with three WHERE statements

    - by jhat
    I am building a note taking app for myself with tag filtering functions, but am having an issue when trying to grab notes with the tags. The tag filter needs to use AND not IN, because it will help better narrow down what I am looking for. My tables are configured like this: + notes note_id | note_title | note_uid + tags tag_id | tag_title + notes_tags nt_id | nt_note_id | nt_tag_id The notes_tags table keeps track of all notes' tags. I am not worried about returning any information about tags, so here is an example LEFT JOIN I am using currently to only get notes with only 1 tag. SELECT * FROM notes_tags LEFT JOIN notes ON note_id = nt_note_id WHERE note_uid IN ( 1 ) AND nt_tag_id = 10 This query runs perfect, it grabs all of the notes with that single tag. However, I am having issues "pinpointing" my notes using a query like this: SELECT * FROM notes_tags LEFT JOIN notes ON note_id = nt_note_id WHERE note_uid IN ( 1 ) AND nt_tag_id = 10 AND nt_tag_id = 11 What am I doing wrong with the syntax?

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  • How to call AJAX API function from Windows App?

    - by stiopa
    Some company is providing me with web-based API for using their services. I have no problem calling this API functions from within web brower: <html xmlns="http://www.w3.org/1999/xhtml"> <head> <script type="text/javascript" src="http://someaddress.com?&key=somekey"></script> <script type="text/javascript"> var object = new SomeObject(); object.SomeFunction(); </script> </head> I am interested in return value of SomeFunction(). How would I get this return value from windows application?

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  • How to do Google Analytics for ajax call in Facebook?

    - by seatoskyhk
    I have a FBML game and need to track all ajax calls. At the bottom of the page, I have this: and in the javascript functions, I put this: Facebook.urchinTracker("/ajaxcallname/"); However, it doesn't work.. and what I found out is that the utmac (the google account id) is empty!!! _uacct is empty! even I set it in the FBML, it is still empty!! and I can't find a way to dynamically set _uacct be my google account ID.. any one has any idea?

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  • [Python] Help me : how i can deal with web page !

    - by Str1k3r
    hello every one... am looking for modules or functions let's me joins in id web !!!! i mean like i told python go to hotmail.com then go to signup ! how i can do that i mean how i can tell python go to hotmail.com then find some thing called signup in source page then i tell him join to him ....etc i hope you understand my idea ! ** am thinking on urllib2 .. maybe it's can do that? am just new in python

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  • Why does OpenGL have to completely break backwards compatablity?

    - by directx
    I'm not sure if this only applies to JOGL or the entire OpenGL project in general. But there seems to be a vast difference between versions 3.x and 2.x; Code that works on one version will not work on another. It looks to me like the library designers intentionally renamed various classes, packages, and functions just to screw up the existing code. I've never seen anything like this before. The problem is I'm not sure which library to use now, and when looking at code it's not so easy to figure out whether it's supposed to run on 2.x or 3.x.

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  • Is pthread_spin_trylock safe inside of sigsegv handler of multithreaded application?

    - by TWMouton
    I am trying to implement a handler that on SIGSEGV will collect some information such as process-id, thread-id and a backtrace and write this information to a file/pipe/socket. The problem lies in that there is the (probably pretty high) possibility that if one thread experienced a SIGSEGV that the others will shortly follow. If two threads happen to make it to the bit of code where they're writing their report out at the same time then they'll interleave their writing (to the same file). I know that I should only be using async-signal-safe functions as detailed in signal(7) I also have seen at least two cases here and video linked in top answer here where others have used pthread_spin_trylock to get around this problem. Is this a safe way to prevent the above problem?

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  • Undefined reference to "func" when compiled with GCC

    - by hotlemontea
    I implement a link list in two files in linklist.h and linklist.c, and I call some functions defined in linklist.h in main function of main.c. linklist.h is included in both linklist.c and main.c. When I compile this program by GCC with Makefile, the error named "undefined reference to xxx" occurs. I think my Makefile is written correctly as below. So what is the possible reason for this linking error CC=gcc CFLAGS= -g -O2 TARGET=target OBJECTS=main.o linklist.o TARGET: $(OBJECTS) $(CC) $(CFLAGS) $(OBJECTS) -o $(TARGET) clean: rm target $(OBJECTS) main.o:linklist.h linklist.o:linklist.h

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  • Boost singleton trouble

    - by Ockonal
    Hi guys, I have some class which uses boost singleton. It calls some function from own c++ library. This library is written in make file as dependence. Now I have another singleton class and it should call first singleton class. After this code I got linkers error about undefined references for functions which are used in first singleton. When I remove calling first singleton class from second the errors remove. Maybe there is something wrong?

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