Array.swap.go: def of Base
Import: import Base
Lines 2466-2478 of Base/base.bend: https://jend.leeeet.dev/read.txt?path=Base/base.bend&start_line=2466&end_line=2478

import Base

# the recursion descends into a subtree, and z says which: the caller
# computes it from the index and the subtree's half size
def Array.swap.go(-T: Type, a: Array<T>, n: U32, +i: U32, v: T, z: Bool) -> Array<T> & T:
  match a z:
    case ALeaf{x} _:
      (ALeaf{v}, x)
    case ANode{xs, ys} True{}:
      +h = U32.shr(n)
      Array.swap.lo(T, ys, Array.swap.go(T, xs, h, i, v, U32.is_lt(i, U32.shr(h))))
    case ANode{xs, ys} False{}:
      +h = U32.shr(n)
      +j = U32.sub(i, h)
      Array.swap.hi(T, xs, Array.swap.go(T, ys, h, j, v, U32.is_lt(j, U32.shr(h))))

Uses (10):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array.swap.hi
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Array.swap.lo
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  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.shr
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.sub