Advantages of std::for_each over for loop

c++ stl foreach coding-style
missingfaktor picture missingfaktor · Jan 12, 2010 · Viewed 116.1k times · Source

Are there any advantages of std::for_each over for loop? To me, std::for_each only seems to hinder the readability of code. Why do then some coding standards recommend its use?

Answer

Thomas Petit picture Thomas Petit · Jan 12, 2010

The nice thing with C++11 (previously called C++0x), is that this tiresome debate will be settled.

I mean, no one in their right mind, who wants to iterate over a whole collection, will still use this

for(auto it = collection.begin(); it != collection.end() ; ++it)
{
   foo(*it);
}

Or this

for_each(collection.begin(), collection.end(), [](Element& e)
{
   foo(e);
});

when the range-based for loop syntax is available:

for(Element& e : collection)
{
   foo(e);
}

This kind of syntax has been available in Java and C# for some time now, and actually there are way more foreach loops than classical for loops in every recent Java or C# code I saw.

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