[Boost-users] transforming vector using map?

13 Oct 2006

      I have a vector of strings and I have a map that maps one string to 
another. How can use transform for that?

This is how I do it right now:

map<string, string> mapping;
vector<string> strings;
for(vector<string>::iterator s=strings.begin();s!=strings.end();++s)
	*s=mapping[*s];

I would like something like:
transform(strings.begin(),strings.end(),strings.begin(),_1=mapping[_1]);

Or maybe there is a predicate that already does it? I can write my own:
template<T> struct mapit: public unary_function<T,T>
{
	map<T,T> mapping;
	mapit(const map<T,T>& m):mapping(m){}
	T operator()(const T& s){return mapping[s];}
}

transform(strings.begin(),strings.end(),strings.begin(),mapit<string>(mapping));

Is it the proper way to do such a transformation?

Thanks.

-- 
Regards,
     Alexander.                http://sjcomp.com

[Boost-users] transforming vector using map?

Alexander Shyrokov