Re: [Boost-users] converting value before inserting into a list

From: Hughes, James (jhughes_at_[hidden])
Date: 2006-09-19 10:02:03

> -----Original Message-----
> From: boost-users-bounces_at_[hidden] 
> [mailto:boost-users-bounces_at_[hidden]] On Behalf Of 
> Alexander Shyrokov
> Sent: 19 September 2006 14:19
> To: boost-users_at_[hidden]
> Subject: [Boost-users] converting value before inserting into a list
> 
> I want to convert values according to a map before inserting 
> it into the list. What is a proper way to do that?
> I have this:
> 
> map<int,int> m;
> vector<int> a,b;
> 
> for(vector<int>const_iterator i=a.begin();i!=a.end();++i)
> 	b.push_back(m[*i]);
> 
> I could use std::copy with std::back_inserter to add elements 
> to b, but how do I convert it first? Should I write my own 
> version of back_inserter for that?
> 
> copy(a.begin(),a.end(),my_back_inserter(b,m));
> 
> Thanks.
> --
> Regards,
>      Alexander.                http://sjcomp.com
> _______________________________________________

I probably being very anti-modern C++ here, but I think that the for
loop takes a lot of beating for readability......its probably the most
efficient too (with a bit of cacheing of invarients)......

I do find that some of these so called 'helpers' do make the code more
obscure, but that's perhaps because I have spent 15 years doing C then
C++, rather than solely starting with C++.

James

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> 

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