Re: C2784 triggered by STL::Set insert() and find()

From:

red floyd <no.spam.here@example.com>

Newsgroups:

comp.lang.c++

Date:

Sun, 12 Oct 2008 17:19:10 -0700

Message-ID:

<VxwIk.2136$pr6.1754@flpi149.ffdc.sbc.com>

Olumide wrote:

Hello,

I've got this nice inner class that I'm holds a set of "FrontPoint"
objects as shown below. Unfortunately, the find and insert methods
trigger massive C2784 errors. Would someone please point out what I'm
doing wrong?

Among other things, you're not posting a minimal compilable example
which exhibits the behavior in question -- see FAQ 5.8 --
http://www.parashift.com/c++-faq-lite/how-to-post.html#faq-5.8

//////////////////////// code ////////////////////////

struct FrontPoint
{
      // stuff
};

class Cell
{
public:
    double xMin , xMax, yMin, yMax , zMin , zMax;
    Cell *upper , *lower , *north, *south, *east , *west;
    Cell::Cell(){ upper = lower = north = south = east = west = NULL; }
    set<FrontPoint > frontPoint;

    void addFrontPoint( FrontPoint& frontPt )
    {
        frontPoint.insert( frontPt ); // Triggers C2784
    }

    void removeFrontPoint( FrontPoint& frontPt )
    {
        set<FrontPoint >::iterator frontPtItx =
frontPoint.find( frontPt ); // Triggers C2784
    }
};

//////////////////////// error ////////////////////////

c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include
\functional(139) : error C2784: 'bool std::operator <(const
std::basic_string<_Elem,_Traits,_Alloc> &,const _Elem *)' : could not
deduce template argument for 'const
std::basic_string<_Elem,_Traits,_Ax> &' from 'const
MarchingTriangles::FrontPoint'

OK, Where and what is MarchingTriangles?
[remainder redacted]