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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33904 91177308-0d34-0410-b5e6-96231b3b80d8
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Chris Lattner 2007-02-05 06:30:51 +00:00
parent 90a2eb02e5
commit 32d84765c8

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@ -797,6 +797,33 @@ rarely be a benefit) or if you will be allocating many instances of the vector
itself (which would waste space for elements that aren't in the container).
vector is also useful when interfacing with code that expects vectors :).
</p>
<p>One worthwhile note about std::vector: avoid code like this:</p>
<div class="doc_code">
<pre>
for ( ... ) {
std::vector<foo> V;
use V;
}
</pre>
</div>
<p>Instead, write this as:</p>
<div class="doc_code">
<pre>
std::vector<foo> V;
for ( ... ) {
use V;
V.clear();
}
</pre>
</div>
<p>Doing so will save (at least) one heap allocation and free per iteration of
the loop.</p>
</div>
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