Logic.none_some: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend as Logic
Lines 80-83 of bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend&start_line=80&end_line=83

import Base

# Maybe discrimination.
def none_some(-A: Data, x: A, e: {None{} == Some{x} : Maybe<&2, A>}) -> Empty:
  %Equal.sym(Maybe<&2, A>, None{}, Some{x}, e) : truth(Maybe.is_some(&2, A, _))
  Unit{}

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Empty
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe.is_some
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Unit
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend&name=truth