Invariants.nonempty: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/proofs/invariants.bend as Invariants
Lines 41-46 of bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/proofs/invariants.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/proofs/invariants.bend&start_line=41&end_line=46

import Base

def nonempty(-V: Data, m: Map<&2, V>) -> Bool:
  match m:
    case MTip{}:
      False{}
    case other:
      True{}

Uses (2):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Map