Implement lambda function for REGEXREPLACE

Question

This would be cool if REGEXREPLACE would have LAMBDA function for further replacement logic. The MatchEvaluator delegate in .NET does this job. The pseudo function would like this:

=REGEXREPLACE("This is regex 123 and 456", "[1-3]+", LAMBDA(match, LET(m, --match, IF(m=123, m*2, m*3)))) So, when regex finds "123" string, it passes it to lambda, which processes this matched value the way it's required. In this case, if match is equal to 123, then it's double, otherwise it's tripled.

Answer 1

In .NET there's overload to Regex.Replace method in which it accepts method with passed Match object into it (MatchEvaluator delegate). You can do any manipulations with a match. Returned string will replace found string. Is it clear now? In Excel terms, it would be LAMBDA function which accepts one argument.

Answer 2

I am not sure if I understand you.

This is a kind of callback.

so pass REGEXREXTRACT("This is regex 123 and 456","[1-3]+",1) as array to reduce may be an option.