Module Tp4::Join2ByFns

A basic, but very flexible join operation, taking a new tuple predicate to join as well as a function for each that maps it to a value of type J.

For instance, given sets of tuples (a, b, c) and (d, e) and join functions (a, b, c) -> a and (d, e) -> e, this module will join both tuple sets on a = e.