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14. Performance Improvements
========================================

- DOM:
. Looping over a DOMNodeList now uses caching. Therefore requesting items no
longer takes quadratic time by default.
. Getting text content from nodes now avoids an allocation, resulting in a
performance gain.

- Standard:
. The file() flags error check is now about 7% faster.

- SPL:
. RecursiveDirectoryIterator now performs less I/O when looping over a
directory.



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