Is your feature request related to a problem or challenge?

The same discussion / reasoning as in #10424.

The inner implementation for these UDFs changes based on the number of parameters passed, but the API of the exported regex::expr_fn::* does not enable that.

Describe the solution you'd like

The same solution as implemented #10469, change the exported expr_fns to take Option<Expr> for optional arguments.

Describe alternatives you've considered

Alternatives discussed in the prior issue:

• change expr_fn to take a Vec instead of explicit arguments
• maintain a different exported expr_fn for each set of non-null parameters

Additional context

No response