Heap.Heap.pop.push_new: law of bend-kit-collections@0.1.4.1
Import: import bend-kit-collections@0.1.4.1/heap.bend as Heap
Lines 109-113 of bend-kit-collections@0.1.4.1/heap.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-collections@0.1.4.1/heap.bend&start_line=109&end_line=113

import Base

# LAW: popping what was pushed onto an empty heap gives it back
law Heap.pop.push_new:
  for -x: U32
  {Heap.pop(~U32, ~U32.is_le, Heap.push(~U32, ~U32.is_le, x, Heap.new(U32)))
   == Some{(x, Heap.new(U32))} : Maybe<&1, U32 & Heap<U32>>}

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Pair
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_le
  https://jend.leeeet.dev/definition.txt?path=bend-kit-collections@0.1.4.1/heap.bend&name=Heap
  https://jend.leeeet.dev/definition.txt?path=bend-kit-collections@0.1.4.1/heap.bend&name=Heap.new
  https://jend.leeeet.dev/definition.txt?path=bend-kit-collections@0.1.4.1/heap.bend&name=Heap.pop
  https://jend.leeeet.dev/definition.txt?path=bend-kit-collections@0.1.4.1/heap.bend&name=Heap.push