utils-string.stanza

defpackage utils/string :
  import core

public defn hex-to-int (s: String) -> Int :
  var res = 0
  for i in 2 to length(s) do :
    val dig = index-of("0123456789ABCDEF", s[i]) as Int
    res = res * 16 + dig
  res

;;; CHARACTERS

public defn trim (s:String, ok?:(Char) -> True|False) -> String :
   match(index-when(ok?, s)) :
      (i:Int) :
         val n = length(s)
         val j = for i in (n - 1) through 0 by -1 find! :
            ok?(s[i])
         s[i through j]   
      (i:False) : ""

defn split-any* (str:IndexedCollection<Char>, any:String, range:Seq<Int>) -> Seq<KeyValue<Int, String>> :
  generate<KeyValue<Int, String>> :
    val beg = next(range)
    let loop (start = beg, i = beg) :
      if empty?(range) :
        if contains?(any, str[i]) :
          yield(start => (to-string $ str[start to i]))
          yield(i => (to-string $ str[i through i]))
          loop(i + 1, i + 1)
        else :
          loop(start, i + 1)
      else if i != start :
        yield(start => (to-string $ str[start to false]))

public defn split-any (str:IndexedCollection<Char>, any:String) -> Seq<KeyValue<Int, String>> :
  generate<KeyValue<Int, String>> :
    let loop (start = 0, i = 0) :
      if i < length(str) :
        if contains?(any, str[i]) :
          yield(start => (to-string $ str[start to i]))
          yield(i => (to-string $ str[i through i]))
          loop(i + 1, i + 1)
        else :
          loop(start, i + 1)
      else if start < length(str) :
        yield(start => (to-string $ str[start to false]))

public defn split* (str:String, s:String) -> Seq<String> :
  generate<String> :
    val strl = length(str)
    val sl = length(s)
    let loop (b = 0) :
      if b < strl :
        match(index-of-chars(str, b to false, s)) :
          (i:Int) :
            yield(str[b to i])
            loop(i + sl)
          (i:False) :
            yield(str[b to false])
      else if b > 0 :
        yield("")