# memo/index.ludic - a module whose @alloc_ok helpers are private: renamed by the module rules, they
# must still be declared at run time (alloc_ok_private.ludic)
module memo
export property Rule { parts: []string = null }
export property Memo { rules: []Rule = new []Rule, ints: []int = new []int }
function kept<T>(xs: []T, v: T) -> void {
  @alloc_ok("a kept list: grows to the most it held")
  push(xs, v)
}
@alloc_ok("a memo miss")
function split(s: string) -> []string {
  let out = new []string
  push(out, s[0 .. 1])
  push(out, s[1 .. 2])
  return out
}
export function memo_miss(m: Memo, f: int) -> void {
  @alloc_ok("the memo keeps a rule per text")
  let r = new Rule { parts: split(`ab{f}`) }
  kept(m.rules, r)
  kept(m.ints, f)
}