Backwards Compatibility
Note: This article was originally published at Planet PHP
on 18 February 2011.
This article was originally published inA php|architect in April 2009 and I published it mostly as it appeared in theA magazine shy of the odd formatting to fit the blog format better and updated a few year references.
Just remember, this article was written a while ago and any references to PHP 4 reflect that, take it with a pinch of salt :-)
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