Cli.env: def of shake@0.7.0.0
Import: import shake@0.7.0.0/src/cli.bend as Cli
Lines 194-197 of shake@0.7.0.0/src/cli.bend: https://jend.leeeet.dev/read.txt?path=shake@0.7.0.0/src/cli.bend&start_line=194&end_line=197

import Base

# this argument, falling back to the env var `var` (clap's `.env`)
def env(aa: Arg, +var: String) -> Arg:
  Arg{+n, +s, +l, kk, +h, +r, Fallback{_e, dd}, cs} = aa
  Arg{n, s, l, kk, h, r, Fallback{Some{var}, dd}, cs}

Uses (4):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=shake@0.7.0.0/src/cli.bend&name=Arg
  https://jend.leeeet.dev/definition.txt?path=shake@0.7.0.0/src/cli.bend&name=Fallback