[boost] std::pair: select1st, select2nd?

From: Malte Starostik (malte_at_[hidden])
Date: 2002-10-02 21:51:12

Hi,

I often face situations where I need to apply an algorithm to the keys or 
values of elements in a map or multimap. SGI's STL implementation provides 
the extensions select1st and select2nd for this, GNU's implementation 
provides them in namespace __gnu_cxx.
I looked hard for something like this in the Boost libraries, but didn't find 
anything. As it's only two small utilities I don't think it would justify an 
own library, but I'm not sure which one would be best to add it to (provided 
that I'm not alone in thinking this would be a useful addition to boost :-})

select1st and select2nd are function objects of which the operator() takes a 
std::pair and returns its first or second value resp.

Would it have a chance if I submitted an implementation?

Regards,
-Malte