def arg

bolt@1.27.0.0 · src/rules/calls.bend:109

import Base
import bolt@1.27.0.0/src/syntax/tree.bend as Tree

109# the nth argument, or nothing
110def arg(as: List<&2, Tree.Node>, nn: Nat) -> Tree.Node:
111  match as nn:
112    case Con{h, t} 0n:
113      h
114    case Con{h, t} 1n+p:
115      arg(t, p)
116    case Nil{} m:
117      Tree.NNil{}