sttp.tapir.typelevel

Allows the definition of binary poly-functions (e.g. for folding over tuples).

Note: the poly-function implementation seen here is merely a stripped down version of what Miles Sabin made available with his awesome shapeless library. All credit goes to him!

Concatenates two parameter lists into one. Each parameter list can be either a single type, or a tuple.

The arity of a type if 0 if it's Unit/Nothing, as these types act as a neutral element in the tuple-concatenation operation that takes place when combining inputs/outputs.

The arity of a type is 1 if it's a "singular" type (as viewed at compile-time; at run-time, the value might in fact be a tuple).

Otherwise, the arity of a tuple.

The arity of type T (if its a tuple), as viewed at compile-time (at run-time, a value that is determined to be a "singular" type, might in fact be a tuple).