reduce number of function calls in t()

If we really want to get rid of t() speed problems, then we can cache the return value of the check done on every t() call, since $languages and module_exists('locale') is not supposed to change in a Drupal run AFAIK. Something like:

static $translate = NULL;

if (!isset($translate)) {
  $translate = ($languages && module_exist("locale"));
}
else {
  $string = ($translate ? t($string) : $string);
}

...

That would only cost an isset() check second and all subsequent times t() is called. This is probably just nitpicking though... I am not sure this would lead to any significant gains... Maybe.

The recursive call to t() is just a typo, I mean locale() :)

I propose to change the implementation of module_exist instead.
Currently it uses isset($list[$name]) which seems fo be slower than function_exists(). We should do a function_exists on a function that every module has. (_help?).

does anyone have any benchmarks to justify the claim of 2x speed increase with this patch?