in-array function

Hi, Any chance the in_array function can be modified to return the key instead of a boolean, perhaps if a third argument were added to ask for that info? Often I like to delete an entry from the array or do something else with it, or use it as a reverse lookup, and as is the function does not help very much. As long as we are on the topic, could it also be possible to pass a Regex as the needle? Ciao, Andreas