Junctions in Raku are cool but at first glance they do not follow the rules for static typing. I was curious about their formal typing semantics, so I deconstructed and then reconstructed junctions from a functional, static typing perspective.
Raku has this neat feature called Junctions. A junction is an unordered composite value. When a junction is used instead of a value, the operation is carried out for each junction element, and the result is the junction of the return values of all those operators. Junctions collapse into a single value when used in a Boolean context. Junctions can be of type all (&), any (|), one (^) or none (empty junction).
For example,
