Regex Tester & Validator

Matches text positioned immediately after a colon and just before an opening parenthesis, using a positive lookbehind for ':' and a positive lookahead for '('. The lazy quantifier (.*?) captures the shortest possible segment, stopping at the first '(' encountered on the line. This is useful for extracting function names, values, or labels from formatted strings such as 'label: handler(args)' or structured log lines, finding all occurrences across multiple lines with the g and m flags.