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POConstructor w/Multiple Arguments in Constructor list not working C++
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copied!<p>I'm trying to compile class A, which has a member of class B, where class B has no default constructor and its only constructor requires multiple arguments. Simple, right? Apparently not...</p> <p>Class A:</p> <pre><code>class SessionMediator { public: SessionMediator() : map_(16,100,100) {} Tilemap map_, background_, foreground_; }; </code></pre> <p>Class B:</p> <pre><code>struct Tile2D; class Tilemap { public: Tilemap(const unsigned int tile_size, const unsigned int width, const unsigned int height) : tiles_(NULL), tile_size_(tile_size) { Resize(width, height); } inline void Resize(const unsigned int width, const unsigned int height) { /* Allocate tiles & assign to width_, height_... */ } unsigned int tile_size_, width_, height_; Tile2D* tiles_; }; </code></pre> <p>I am instantiating SessionMediator like so:</p> <pre><code>int main(int argc, char** argv) { SessionMediator session; return 0; } </code></pre> <p>This is the error I am getting. I'm compiling in XCode on Mac OS 10.5.8 and the compiler is g++:</p> <pre><code>session_mediator.h: In constructor 'SessionMediator::SessionMediator()': session_mediator.h:19: error: no matching function for call to 'Tilemap::Tilemap()' tilemap.h:31: note: candidates are: Tilemap::Tilemap(unsigned int, unsigned int, unsigned int) tilemap.h:26: note: Tilemap::Tilemap(const Tilemap&) session_mediator.h:19: error: no matching function for call to 'Tilemap::Tilemap()' tilemap.h:31: note: candidates are: Tilemap::Tilemap(unsigned int, unsigned int, unsigned int) tilemap.h:26: note: Tilemap::Tilemap(const Tilemap&) (Duplicate of above here) Build failed (2 errors) </code></pre> <p>I wrote a short compilable example doing basically the same thing, to try to figure out what exactly I was doing wrong, which compiles just fine with no errors in g++:</p> <pre><code>class A { public: A(int x, int y, int z) : x_(x), y_(y), z_(z) {} int x_, y_, z_; }; class B { public: B() : m_a(1,2,3) {} A m_a; }; int main(int argc, char **argv) { B test; return 0; } </code></pre> <p>Why does it fail in the first example? The 3 arg constructor for Tilemap (in Ex#1) is being called in the same way that the 3 arg constructor for A is being called (in Ex#2).</p> <p>The code seems pretty much identical to me in the two examples.</p>

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