"test1.cc", line 61: error: nonstandard form for taking the address of a
member function
b.sqr(ff,foo::g,2.0); // CINT does not understand foo::g
^
2 errors detected in the compilation of "test1.cc".
--------------------------------------------------------------------------------
Regards, Pasha.
Jonathan M. Gilligan writes:
> I need to have a function that accesses an arbitrary member function of a
> class through a pointer (I need to integrate member functions and don't
> want to write a separate integration routine for each function that I want
> to integrate. I can't use the TF1::Integrate because the functions I need
> to integrate are pure virtual member functions of an abstract base class.
> The ARM indicates that the right way to go with this in standard C++ is to
> use the pointer-to-member operators .* and ->* (ARM section 5.5). However,
> CINT does not seem to implement these operators (see test program below).
>
> I would like to request that a future release implement these operators and
> to ask whether there is a workaround. Can I call a member function of a
> class through a pointer in CINT?
>
> The following program runs perfectly under my regular C++ compiler (M'Soft
> VC++ 5.0 SP3). However under Root's CINT I get these error messages:
>
> Error: No symbol foo::f in current scope FILE:boo.cpp LINE:56
> Error: class,struct,union or type fu.*fn not defined FILE:boo.cpp LINE:47
> Error: No symbol foo::g in current scope FILE:boo.cpp LINE:57
> Error: class,struct,union or type fu.*fn not defined FILE:boo.cpp LINE:47
>
> //====================== boo.cpp ========================
> class foo
> {
> private:
> public:
> foo();
> ~foo();
> virtual double f(double x) const;
> virtual double g(double x) const;
> };
>
> class bar
> {
> public:
> bar();
> ~bar();
> double sqr(const foo& fu, double (foo::*fn)(double) const, double x) const;
> };
>
> foo::foo()
> {
> }
>
> foo::~foo()
> {
> }
>
> double foo::f(double x) const
> {
> return x + 1.0;
> }
>
> double foo::g(double x) const
> {
> return 2.0 * x;
> }
>
> bar::bar()
> {
> }
>
> bar::~bar()
> {
> }
>
> double bar::sqr(const foo& fu, double (foo::*fn)(double) const, double x)
> const
> {
> double y = (fu.*fn)(x); // CINT does not seem to understand the .*
> operator here
> return y * y;
> }
>
> void boo ()
> {
> bar b;
> foo ff;
>
> b.sqr(ff,foo::f,2.0); // CINT does not understand foo::f (ptr to member
> function)
> b.sqr(ff,foo::g,2.0); // CINT does not understand foo::g
> }
> //===================================== end of boo.cpp
> =================================
> ===========================================================================
> Jonathan M. Gilligan <jonathan.gilligan@vanderbilt.edu>
> Research Assistant Professor and Associate Director (615) 343-2957
> Center for Molecular and Atomic Studies at Surfaces Fax: 343-1708
> Dept. of Physics and Astronomy, Box 1807-B Sec'y 322-6438
> Vanderbilt University, Nashville, TN 37235 Lab: 343-7578