ChunkColumn.vacancy_selected: def of bendvy-ecs-core@0.1.0.3
Import: import bendvy-ecs-core@0.1.0.3/chunk_column.bend as ChunkColumn
Lines 68-72 of bendvy-ecs-core@0.1.0.3/chunk_column.bend: https://jend.leeeet.dev/read.txt?path=bendvy-ecs-core@0.1.0.3/chunk_column.bend&start_line=68&end_line=72

import Base

def vacancy_selected(-S:Data,-C:Type,column:Column<S,C>,+index:U32,selected:Bool) -> Column<S,C> & Maybe<&2,Bool>:
  match column selected:
    case column False{}:(column,None{})
    case Leaf{values,stamps} True{}:vacancy_values(S,C,stamps,index,Array.size(Maybe<&1,C>,values))
    case Branch{+half,left,right} True{}:vacancy_join(S,C,half,vacancy_selected(S,C,left,index,U32.is_lt(index,half)),vacancy_selected(S,C,right,U32.sub(index,half),Bool.not(U32.is_lt(index,half))))

Uses (12):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array.size
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.not
  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_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.sub
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/chunk_column.bend&name=Column
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/chunk_column.bend&name=vacancy_join
  https://jend.leeeet.dev/definition.txt?path=bendvy-ecs-core@0.1.0.3/chunk_column.bend&name=vacancy_values