Re: std::for_each + break

From:
Sohail Somani <sohail@taggedtype.net>
Newsgroups:
comp.lang.c++
Date:
Wed, 21 Nov 2007 01:46:31 GMT
Message-ID:
<X5M0j.1913$HH2.1044@edtnps82>
On Wed, 21 Nov 2007 01:38:22 +0000, Sohail Somani wrote:

On Tue, 20 Nov 2007 17:18:24 -0800, Kai-Uwe Bux wrote:

However, it does not actually present any data in support of the claim
that generic algorithms tend to introduce the kind of bug you pointed
out.


I'm done with this thread, but I just want to point out that there was
no bug. That is an intended mode of use for std::transform: Perform an
operation on each element in an array and assign it to another.


Damnit, here you go.

// file.cpp
#include <iostream>
#include <vector>
#include <boost/lambda/lambda.hpp>
#include <algorithm>

namespace bl = boost::lambda;

int main()
{
        std::vector<int> v1(10,5);
        std::vector<int> v2(10);
        // v2[i] = v1[i] + 1 for i in [0,v2.size())
        std::transform(v1.begin(),v1.end(),v2.begin(),bl::_1 + 1);
        std::for_each(v1.begin(),v1.end(),std::cout << bl::_1 << '\n');
        std::for_each(v2.begin(),v2.end(),std::cout << bl::_1 << '\n');
}

Output:
5
5
5
5
5
5
5
5
5
5
6
6
6
6
6
6
6
6
6
6

--
Sohail Somani
http://uint32t.blogspot.com

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