Appendix B. Additional New Features and Minor Changes
This appendix covers the changes made in
PHP 5 that arenât documented elsewhere in the book.
Some sections discuss new features, such as the command-line
processing options. Other sections contain slight modifications of
existing features, such as what happens when you incorrectly treat a
string as an array, or how strrpos( )
handles its
needle. These fixes will trip you up if youâre
relying on PHP 4 behavior.
Passing Optional Parameters by Reference
You can now pass optional parameters by reference. For example:
function updateAddress(&$address = 'NULL') { }
In PHP 4, you could declare a parameter as either optional or pass-by-reference, but not both. PHP 5 removes this limitation.
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