The best part is the echo vs. print stuff was axed in deference to people noticing

If it’s not in a loop or not recursive, it’s probably not worth looking at.

A few things I’ve also noticed:
Using references in PHP can actually slow things down. Even I make this mistake because I’m used to compiled languages that actually do what they’re told. I’m not sure with respect to “quasi-return by reference” vs. return. However, if it doesn’t need to be a reference because you’re not actually modifying it, *do not use reference passing.* Doing so actually slows things down. Why? PHP won’t copy it anyway if you don’t modify it, so you’re actually making it track/do more. I didn’t believe it at first … but it makes sense.

Also. ” vs. ‘

Anyone who has looked at the PHP lexer knows that the interpolated variables are pulled out by the lexer itself. Using a single quoted string vs. a double quoted string without variables will only speed things up to the extent that the lexer does not have to check for a variable. This will not be measurable.

I don’t know why, but deep recursion may be a problem for PHP sometimes. On the other hand, the function I’m referring to is only anecdotal as was rewritten a far less stupid way

I think what bothers me most about php.net is seeing meaningless profiling/tests of things that don’t matter.

Look at loops. Look at a Donald Knuth book. Seriously, no matter how much you optimize a bubblesort, it’s still a bubblesort.

Consider this a love letter to cancel out the hate mail