🍵 Matcha - first-class match specifications for Elixir

[christhekeele]

@zachallaun

you’d need to be able to specify “higher order” specs of some kind that explicitly declare the “vars” or whatever that you’re replacing

Yep, this is my intuition about such a feature; I’m not aiming at supporting it mostly because that’s beyond the scope of normal matchspec usage.

@hst337

I meant something like

merge(spec(do: [head | _] -> head), spec(do: {left, right} -> left + right))

To result in

spec(do: [{left, right} | _] -> left + right)

The behaviour here seems rather undefined, I can think of dozens of ways to approach embedding complicated matchspecs in each other.