User:Niaht Nakamichi/PHP Code

is_uuid

<php> function is_uuid($uuid) { if (strlen($uuid) !== 36) return false; if (strpos($uuid, '-') !== 8) return false; if (strpos($uuid, '-', 24) !== false) return false; if (strpos($uuid, '-', 9) !== 13) return false; if (strpos($uuid, '-', 13) !== 13) return false; if (strpos($uuid, '-', 14) !== 18) return false; if (strpos($uuid, '-', 18) !== 18) return false; if (strpos($uuid, '-', 19) !== 23) return false; if (strpos($uuid, '-', 23) !== 23) return false; if (ctype_xdigit(str_replace('-', , $uuid)) == false) return false; return true; } </php>

A somewhat slower version using substr_count:

<php> function is_uuid2($uuid) { if (strlen($uuid) !== 36) return false; if (substr_count($uuid, '-') !== 4) return false; if (strpos($uuid, '-') !== 8) return false; if (strpos($uuid, '-', 9) !== 13) return false; if (strpos($uuid, '-', 14) !== 18) return false; if (strpos($uuid, '-', 19) !== 23) return false; if (ctype_xdigit(str_replace('-', , $uuid)) == false) return false; return true; } </php>

Results

 	time index	ex time	%
Start	1217369864.26464800	-	0.00%
double strpos checks	1217369864.34994000	0.085292	50.32%
substr_count	1217369864.43412200	0.084182	49.67%
Stop	1217369864.43413600	0.000014	0.01%
total	-	0.169488	100.00%