Bytes.Cursor.region.if: def of bend-kit-bytes@0.3.3.0
Import: import bend-kit-bytes@0.3.3.0/bytes.bend as Bytes
Lines 849-857 of bend-kit-bytes@0.3.3.0/bytes.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&start_line=849&end_line=857

import Base

# On success, read inside the region, then leave with the returned affine limit.
def Cursor.region.if(ok: Bool, c: Cursor, +n: U32) -> Cursor & Maybe<&1, CursorLimit>:
  match ok:
    case False{}:
      (c, None{})
    case True{}:
      Cursor{b, +pos, start, end} = c
      +resume = (pos + n : U32)
      (Cursor{b, pos, pos, resume}, Some{CursorLimit{resume, start, end}})

Uses (8):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  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.add
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=Cursor
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bytes@0.3.3.0/bytes.bend&name=CursorLimit