Str.text.replace.at: def of ezsys@0.1.0.0
Import: import ezsys@0.1.0.0/src/str.bend as Str
Lines 86-99 of ezsys@0.1.0.0/src/str.bend: https://jend.leeeet.dev/read.txt?path=ezsys@0.1.0.0/src/str.bend&start_line=86&end_line=99

import Base

# a nonempty `old` at this character, or not: write `new` and pass over
# the rest of `old`, or write the character
def text.replace.at(
  hit: Bool,
  hd: Char,
  +new: String,
  +left: Nat,
  next: Nat -> String
) -> String:
  match hit:
    case True{}:
      new ++ next(left)
    case False{}:
      SCon{hd, next(0n)}

Uses (5):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Char
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String.append