[Boost-users] [Multiindex] Const_mem_fun from base class

From: Francesco Biscani (bluescarni_at_[hidden])
Date: 2007-05-20 09:12:19

Hello,

I get an error when I'm trying to use a const member function in a multi-index 
container, as a template parameter for indexed_by<>. This const member 
function comes from a base class, from which the class contained in the 
multiindex container is derived. The error is the following:

/home/yardbird/documenti/work/prog/piranha/pyranha/Gsp/../../src/polynomial.h:41: 
error: could not convert template 
argument ‘&piranha::base_monomial_gmp_array<piranha::double_cf>::get_degree’ 
to ‘int (piranha::monomial_gmp_array<piranha::double_cf>::*)()const’

The member function is named "get_degree", and returns an integer. The base 
class is "base_monomial_gmp_array", the derived class is, 
unsurprisingly, "monomial_gmp_array". If I "lift" this function to the 
derived class, by re-defining it there, the problem disappears.

I have a hunch that probably with some clever typedef or some static_cast 
wizardy this could be resolved, however my experiments have not resolved 
anything yet. Does anyone have an idea on how to proceed?

Thanks in advance,

  Francesco Biscani.