Args.at: def of ezx@1.11.0.0
Import: import ezx@1.11.0.0/src/share/args.bend as Args
Lines 48-57 of ezx@1.11.0.0/src/share/args.bend: https://jend.leeeet.dev/read.txt?path=ezx@1.11.0.0/src/share/args.bend&start_line=48&end_line=57

import Base

# the nth argument, or "" when it was not given. Both the list and the count
# are scrutinised together, so the walk needs no helper to branch through.
def at(xs: List<&2, String>, index: Nat) -> String:
  match xs index:
    case Nil{} _m:
      ""
    case Con{h, _t} 0n:
      h
    case Con{_h, t} 1n+p:
      at(t, p)

Uses (3):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String