List.is_empty_map_sym: law of bend-mathlib@0.8.1.0
Import: import bend-mathlib@0.8.1.0/list.bend as List
Lines 3034-3040 of bend-mathlib@0.8.1.0/list.bend: https://jend.leeeet.dev/read.txt?path=bend-mathlib@0.8.1.0/list.bend&start_line=3034&end_line=3040

import Base

# A map is empty exactly when the list is, reversed to rewrite toward the simple side.
law is_empty_map_sym:
  for ~A: Type
  for ~B: Type
  for ~f: A -> B
  for xs: List<A>
  {List.is_empty(&1, A, xs) == List.is_empty(&1, B, List.map(~A, ~B, ~f, xs)) : Bool}

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.is_empty
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.map
  https://jend.leeeet.dev/definition.txt?path=bend-mathlib@0.8.1.0/list.bend&name=is_empty_map