Posted by Edward Z. Yang on 05/19/07 18:23

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Ciaran wrote:
> All great ideas guys! Thanks for the replies on this. I especially
> like purcaholic's one! Anyone know which of these methods would be the
> fastest? Are any of them actually any faster than the basic one I
> posted at the start?

Purcaholic's one doesn't work (as it stands: he probably mean to use
strpos) and is probably the slowest.

In terms of speed, it's probably like this (from fastest to slowest):

1. Original method
2. isset($lookup[$var])
3. in_array
4. strstr

If you have a particularly large set of numbers to compare against,
method 2 may end up being faster due to the implementation of
associative arrays needing only a binary search. I would use method 2
simply because it's more maintainable (you can generate the $lookup
array from anywhere you want).

But I should warn you: this is really premature optimization and will
make no difference at all most of the time.

- --
Edward Z. Yang GnuPG: 0x869C48DA
HTML Purifier <htmlpurifier.org> Anti-XSS HTML Filter
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