Question

So I have a regex that breaks a string apart that assumes camelCase or PascalCase and converts it into lowercase_with_underscores. That regex looks like this (php):

strtolower(preg_replace('/(?!^)[[:upper:]]/','_\0', $string));

I want to modify this so that it will be able to also break up the string where it assume a string of capitalizes in a row as one unit. For example, I would to be able to break up the following strings:

'GUID' => 'guid'
'SOME_VALUES' => 'some_value'
'someThingELSE' => 'some_thing_else'

Any suggestions on how to modify the regex to do this?

Answer 1

How about:

$result = strtolower(preg_replace('/([a-z])([A-Z])/', '$1_$2', $string));