Search Results

Search found 3679 results on 148 pages for 'definition'.

Page 93/148 | < Previous Page | 89 90 91 92 93 94 95 96 97 98 99 100  | Next Page >

  • Using generic type from other generic parameter

    - by DEHAAS
    Hi, I have a question about .net generics. Consider the following code: public class Test<TKey> { TKey Key { get; set; } } public class Wrapper<TValue, TKey> where TValue : Test<TKey> { public TValue Value { get; set; } } Now, when using this code, I could do something like this: Wrapper<Test<int>, int> wrapper = new Wrapper<Test<int>, int>(); The int type parameter has to be provided twice. Is it possible to modify the Wrapper definition, to require TValue to be a generic type, and use this 'nested' generic type parameter insted of the TKey type parameter?

    Read the article

  • c++ compilation error

    - by clamp
    hello, i got a compile error which i do not understand. i have a h/cpp file combination that does not contain a class but just defines some utility functions. when i try to use a struct that is defined in another class i get the error: error C2027: use of undefined type so, stripped down to the problem, the h file looks like this namespace A { void foo(B::C::SStruct const & Var); } the definition of SStruct is in a class which is in another h-file, that is of course included. namespace B { Class C { struct SStruct { }; } } what am i missing here? thanks!

    Read the article

  • How can I execute a block of code exactly once in PHP?

    - by Jack
    I have one main.php file with a class definition. Other php files use this main.php file //main.php <?php class A{ } //I want to execute the following statements exactly once $a = new A(); /* Some code */ ?> I use main.php in other php files like //php1.php <?php require_once("main.php"); $b = new A(); /* Some code */ ?> Is there any statement in PHP like execute_once()? How do I solve this?

    Read the article

  • .NET's double.NaN - how does this counterintuitive feature work?

    - by GeReV
    I stumbled upon the definition of double.NaN in code: public const double NaN = (double)0.0 / (double)0.0; This is done similarly in PositiveInfinity and NegativeInfinity. double.IsNaN (with removing a few #pragmas and comments) is defined as: [Pure] [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] public static bool IsNaN(double d) { if (d != d) { return true; } else { return false; } } This is, by far, the most counterintuitive thing I have ever seen in the .NET framework. How is 0.0 / 0.0 represented "behind the scenes"? How can division by 0 be possible in double, and why does NaN != NaN?

    Read the article

  • width:auto for <input> fields

    - by richb
    Newbie CSS question. I thought 'width:auto' for a display:block element meant 'fill available space'. However for an <input> element this doesn't seem to be the case. For example: <body> <form style='background-color:red'> <input type='text' style='background-color:green;display:block;width:auto'> </form> </body> Two questions then: Is there a definition of exactly what width:auto does mean? The CSS spec seems vague to me, but maybe I missed the relevant section. Is there a way to achieve my expected behaviour for a input field - ie. fill available space like other block level elements do? Thanks!

    Read the article

  • Filtering SQLAlchemy query on attribute_mapped_collection field of relationship

    - by bsa
    I have two classes, Tag and Hardware, defined with a simple parent-child relationship (see the full definition at the end). Now I want to filter a query on Tag using the version field in Hardware through an attribute_mapped_collection, eg: def get_tags(order_code=None, hardware_filters=None): session = Session() query = session.query(Tag) if order_code: query = query.filter(Tag.order_code == order_code) if hardware_filters: for k, v in hardware_filters.iteritems(): query = query.filter(getattr(Tag.hardware, k).version == v) return query.all() But I get: AttributeError: Neither 'InstrumentedAttribute' object nor 'Comparator' object associated with Tag.hardware has an attribute 'baseband The same thing happens if I strip it back by hard-coding the attribute, eg: query.filter(Tag.hardware.baseband.version == v) I can do it this way: query = query.filter(Tag.hardware.any(artefact=k, version=v)) But why can't I filter directly through the attribute? Class definitions class Tag(Base): __tablename__ = 'tag' tag_id = Column(Integer, primary_key=True) order_code = Column(String, nullable=False) version = Column(String, nullable=False) status = Column(String, nullable=False) comments = Column(String) hardware = relationship( "Hardware", backref="tag", collection_class=attribute_mapped_collection('artefact'), ) __table_args__ = ( UniqueConstraint('order_code', 'version'), ) class Hardware(Base): __tablename__ = 'hardware' hardware_id = Column(Integer, primary_key=True) tag_id = Column(String, ForeignKey('tag.tag_id')) product_id = Column(String, nullable=True) artefact = Column(String, nullable=False) version = Column(String, nullable=False)

    Read the article

  • 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!

    Read the article

  • ASP.NET MVC CHECKBOXES PROBLEM

    - by mazhar
    CONTROLLER public ActionResult Index() { GroupRepository grouprepository = new GroupRepository(); ViewData["Group"] = grouprepository.FindGroups(); return View(); } <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage" % <% foreach (Group i in ViewData["Group"] as List) { % " checked="checked" / <% } % The thing is that it is not able to find group id and displaying the following error. What is the solution? CS1061: 'System.Text.RegularExpressions.Group' does not contain a definition for 'int_GroupId' and no extension method 'int_GroupId' accepting a first argument of type 'System.Text.RegularExpressions.Group' could be found (are you missing a using directive or an assembly reference?)

    Read the article

  • Scope of Constants in Ruby Modules

    - by user204078
    I'm having a little problem with constant scope in mixin modules. Let's say I have something like this module Auth USER_KEY = "user" unless defined? USER_KEY def authorize user_id = session[USER_KEY] def end The USER_KEY constant should default to "user" unless it's already defined. Now I might mix this into a couple of places, but in one of those places the USER_KEY needs to be different, so we might have something like this class ApplicationController < ActionController::Base USER_KEY = "my_user" include Auth def test_auth authorize end end I would expect that USER_KEY would be "my_user" when used in authorize, since it's already defined, but it's still "user", taken from the modules definition of USER_KEY. Anyone have any idea how to get authorize to use the classes version of USER_KEY?

    Read the article

  • Why does a non-constant offsetof expression work?

    - by Chris J. Kiick
    Why does this work: #include <sys/types.h> #include <stdio.h> #include <stddef.h> typedef struct x { int a; int b[128]; } x_t; int function(int i) { size_t a; a = offsetof(x_t, b[i]); return a; } int main(int argc, char **argv) { printf("%d\n", function(atoi(argv[1]))); } If I remember the definition of offsetof correctly, it's a compile time construct. Using 'i' as the array index results in a non-constant expression. I don't understand how the compiler can evaluate the expression at compile time. Why isn't this flagged as an error?

    Read the article

  • How to pass multiple params to function in python?

    - by user1322731
    I am implementing 8bit adder in python. Here is the adder function definition: def add8(a0,a1,a2,a3,a4,a5,a6,a7,b0,b1,b2,b3,b4,b5,b6,b7,c0): All function parameters are boolean. I have implemented function that converts int into binary: def intTObin8(num): bits = [False]*8 i = 7 while num >= 1: if num % 2 == 1: bits[i] = True else: bits[i] = False i = i - 1 num /= 2 print bits return [bits[x] for x in range(0,8)] I want this function to return 8 bits. And to use this two functions as follows: add8(intTObin8(1),intTObin8(1),0) So the question is: How to pass 8 parameters using one function?

    Read the article

  • C++ Vector of vectors

    - by xbonez
    I have a class header file called Grid.h that contains the following 2 private data object: vector<int> column; vector<vector<int>> row; And a public method whose prototype in Grid.h is such: int getElement (unsigned int& col, unsigned int& row); The definition of above mentioned function is defined as such in Grid.cpp: int getElement (unsigned int& col, unsigned int& row) { return row[row][col] ; } When I run the program, I get this error: error C2109: subscript requires array or pointer type Whats going wrong?

    Read the article

  • Creating new Entities from Stored Procedure

    - by SK
    I have a stored procedure that retrieves existing rows from a table and also creates includes new rows that match the table definition and mapped entity (.net 3.5 entity framework). These new rows are not written to the database in the stored procedure. The stored procedure executes, but the new rows that were created will not load the navigation properties sucessfully i.e. the rows that do not actually exist in the database. e.g. database rows: key, data, FK 1, xxx, a 2, xxx, b returned rows from stored procedure: key, data, FK 1, xxx, a 2, xxx, b 3, yyy, a 4, yyy, b The entity will load FK entities a and b for rows 1 and 2, but for rows 3 and 4 the FK entity is null. Do I somehow need to add the new rows to the data context? or turn off tracking?

    Read the article

  • How should I make up for the lack of static initializers in PHP?

    - by kahoon
    I'm thinking about putting every class into a separate file and doing the static initialization outside of the class definition. The problem with this is the fact that the initialization will happen before the said class is actually needed (it will happen when the file which contains the class is included for the first time). It's a problem, because it may happen that the class won't be used at all, hence the initialization is unnecessary. And I think the practice of including the used files not in the beginning of your code is simply a dirty technique. If anybody has a viable solution to this problem, I would greatly appreciate it.

    Read the article

  • implementing runat in HtmlTextWriterAttribute

    - by user525116
    Hi dear friends, I have a custom asp.net control. public class Window : WebControl { protected override void RenderContents(HtmlTextWriter wr) { wr.AddAttribute("runat", "server",true); wr.AddAttribute("id", this.UniqueID, false); wr.RenderBeginTag(HtmlTextWriterTag.Div); wr.RenderEndTag(); wr.WriteLine(); base.RenderContents(wr); } } And this is my result after compile and use the control: <cc1:Window ID="Window1" runat="server" /> Use standard definition DIV with standard format: <div runat="server" id="aaaa"></div> After compile my web page to use this web custom control, this is render browser source of my web page: <span id="Window1"><div runat="server" id="Window1"></div></span> <div id="aaaa"></div>

    Read the article

  • [PHP] Variables loaded from a separate script are not defined within functions

    - by Goro
    Hello, I use settings.php to store general settings for my application. When I load this settings file, I can use the variables defined in settings.php in the script itself, but not within any functions I define in it. For example, in my class definition, myclass.php: <?php $preIP = dirname(__FILE__); require_once( "preIP/settings.php" ); class MyClass { ... public function foo() { echo $variable_from_settings; } } The code in the function foo() will not work (the variable will not be defined). The settings.php file looks like this: $variable_from_settings = "bar"; Thanks,

    Read the article

  • How does make_pair know the types of its args?

    - by bobobobo
    The definition for make_pair in the MSVC++ "utility" header is: template<class _Ty1, class _Ty2> inline pair<_Ty1, _Ty2> make_pair(_Ty1 _Val1, _Ty2 _Val2) { // return pair composed from arguments return (pair<_Ty1, _Ty2>(_Val1, _Val2)); } I use make_pair all the time though without putting the argument types in angle brackets: map<string,int> theMap ; theMap.insert( make_pair( "string", 5 ) ) ; Shouldn't I have to tell make_pair that the first argument is std::string and not char* ? How does it know?

    Read the article

  • What exactly is a variable in C++?

    - by FredOverflow
    The standard says A variable is introduced by the declaration of an object. The variable's name denotes the object. But what does this definition actually mean? Does a variable give a name to an object, i.e. are variables just a naming mechanism for otherwise anonymous objects? Or is a variable the name itself? Or is a variable a named object in the sense that every variable is also an object? Or is a variable just a "proxy" with a name that "delegates" all operations to the real object? To confuse things further, many C++ books seem to treat variables and objects as synonyms. What is your take on this?

    Read the article

  • Python profiler and CPU seconds

    - by dude
    Hey, I'm totally behind this topic. Yesterday I was doing profiling using Python profiler module for some script I'm working on, and the unit for time spent was a 'CPU second'. Can anyone remind me with the definition of it? For example for some profiling I got: 200.750 CPU seconds. What does that supposed to mean? At other case and for time consuming process I got: -347.977 CPU seconds, a negative number! Is there anyway I can convert that time, to calendar time? Cheers,

    Read the article

  • Multiple inclusion of header file c++

    - by iSight
    Hi, I have a problem regarding multiple inclusion of header file in C++ code. say for example, i have three class X,Y,Z. X and Y are derived from Base class Z. And i want to create an instance of X in Y. The code will go like this. class Z{some code} class X:public Z{some code};//here #include header of class Z added class Y:public Z //here #include header of class Z added as well as of X class {private: X* mX;//instance of X some code}; So in this multiple definition of all methods of base class arises. how can i cope with this problem

    Read the article

  • Is there a method I can override on a JavaScript object to control what is displayed by console.log?

    - by agnoster
    I'm thinking in particular of Chrome, though Firebug would be interesting to. I've tried toString() and valueOf(), but neither of those seem to be used. Interestingly, if I take a function it'll display the function definition - but then if I add a toString() method it will show null! var a = function(){}; console.log(a); // output: function (){} a.toString = function(){ return 'a'; }; console.log(a); // output: null a.valueOf = function(){ return 'v'; }; console.log(a); // output: null Any ideas?

    Read the article

  • Compare two integer arrays with same length

    - by meta
    [Description] Given two integer arrays with the same length. Design an algorithm which can judge whether they're the same, the definition of "same" is that, if these two arrays are in sorted order, the elements in corresponding position should be the same. [Example] <1 2 3 4> = <3 1 2 4> <1 2 3 4> != <3 4 1 1> [Limitation] The algorithm should require constant extra space, and O(n) running time.

    Read the article

  • Visual C++ CreateThread Parameter Problem

    - by Vanwaril
    I have a class that contains a function that calls create thread, and needs to pass itself (this) as a parameter: DWORD threadId; HANDLE h = CreateThread( NULL, 0, runThread, this, 0, &threadId); My runThread definition is as follows: DWORD WINAPI runThread(LPVOID args) { Obj *t = (Obj*)args; t->funct(); return 0; } Unfortunately, the object t that I get in runThread() gets garbage. My Obj class has a function pointer attribute. Could that be the problem? class Obj{ void(*funct)(); and in the constructor: Obj(void(*f)()) { funct = f; } where is my mistake? The function pointer, the createThread itself, or type-casting? I tried whatever I could think of.

    Read the article

  • [Android] Returning to a ListView with a text filter

    - by sosiouxme
    I enabled text filtering on my ListView in the expected way; adding android:textFilterEnabled=”true” in resource definition and (as I'm using a SimpleCursorAdapter) setting a FilterQueryProvider that provides a filtered cursor like so: public Cursor runQuery(CharSequence constraint) { Cursor cur = mDba.fetchTrackers(mCurrentGroupId, constraint.toString()); startManagingCursor(cur); return cur; } My question is this: once the user selects a list item, goes off to another activity, and returns to this one, how can I control the state of the filter previously applied? What I'm seeing right now is that when I return to the activity, the cursor being used is the unfiltered one set on the filter at creation, but the filter text they typed is still shown (and typing keys causes the filter to be applied). What I'd like to do is either clear the filter, or keep the filtered cursor that the activity was left with.

    Read the article

  • How do I remove line references in generate output in doxygen?

    - by MeThinks
    I want to remove lines look as follows but I still want to return source code browsing Definition at line 377 of file xxx.h. I have tried the following two in the doxygen config file but these just remove cross references on types # If the REFERENCES_RELATION tag is set to YES # then for each documented function all documented entities # called/used by that function will be listed. REFERENCES_RELATION = NO # If the REFERENCES_LINK_SOURCE tag is set to YES (the default) # and SOURCE_BROWSER tag is set to YES, then the hyperlinks from # functions in REFERENCES_RELATION and REFERENCED_BY_RELATION lists will # link to the source code. Otherwise they will link to the documentation. REFERENCES_LINK_SOURCE = NO update: I've just trying setting the following and seems to do the jobs but waiting to confirm if this is the correct way of achieving what I want SOURCE_BROWSER = NO

    Read the article

< Previous Page | 89 90 91 92 93 94 95 96 97 98 99 100  | Next Page >