Dear All,

I am trying to use the Str module to match regular expressions. I want to return the longest match.

let txt = "ab"

let reg = "a\\|ab"

let _ =

let b = Str.string_match (Str.regexp reg) txt 0 in

Str.matched_string txt

After the last line, the string "a" is apparently matched. But I hope that the result should be "ab". If I reverse the order of the alternatives in the regular expression, the string "ab" is matched. I don't want the order of the alternatives to matter. What am I doing wrong? What can I do to match the longest substring?

Thanks

Tom