boost::function syntax

From: shyamemani (shyamemani_at_[hidden])
Date: 2003-08-25 15:44:03

Hello everyone,
        I was looking at the boost::function preferable syntax.  

boost::funcion<float (int,int) >

       I also see that this has also been accepted by the standard 
for future STL implementation. The C++ grammar for template 
declaration is as stated below:

template-argument-list:
        template-argument
        template-argument-list , template-argument

template-argument:
        assignment-expression
        type-id
        id-expression

None of the 'declaration' rules also seem to parse the tokens 'float 
(int,int) (I know I am missing something here).
I could not figure out why the string 'float (int,int)' is accepted 
by the compiler and what type it is assigned?  Is it just a extension 
of the standard by GCC?  Can somebody help me figure this out?

Thanks,
Shyam