MODULE Text;

/* A template for the Text 
   interface to be read in Button 
   or Public view only. */

(* The built-in Juno Text module. A 
   Juno text string is a zero-based 
   sequence of characters. *)

(* The variables "t", "u", and "tu" 
   are texts; "i", "n", and "ch" 
   are integers; and "r" is an 
   arbitrary number. *)

PROC tu := Cat(t, u) IS SKIP END;

(* Returns the concatenation of "t" 
   and "u". *)

PROC n := Length(t) IS SKIP END;

(* Returns the number of characters 
   in "t". *)

PROC u := Sub(t, i, n) IS SKIP END;

(* Returns a subsequence of "t" 
   starting at character "i" of 
   length at most "n". The result 
   is empty if "i >= Length(t)" or 
   if "n = 0"; otherwise, it ranges 
   from "i" to "MIN(i+n, 
   Length(t)-1)". *)

PROC ch := GetChar(t, n) IS 
  SKIP 
END;

(* Returns the integer code of 
   character "n" of "t". It is a 
   checked run-time error if "n < 
   0" or "n >= Length(t)". *)

PROC t := FromChar(ch) IS SKIP END;

(* Returns a string of length one 
   containing the character with 
   code "ch". It is a checked 
   run-time error if "ch < 0" or 
   "ch > 255". *)

PROC t := FromNum(r, n) IS SKIP END;

(* Returns the unparsing of the 
   number "r" to "n" digits of 
   precision. *)

PROC i := FindChar(t, ch) IS 
  SKIP 
END;

(* Returns the index of first 
   occurrence of the character "ch" in 
   the text "t", or -1 if "ch" does 
   not occur in "t". It is a 
   checked run-time error if "ch < 
   0" or "ch > 255". *)

PROC i := FindCharR(t, ch) IS 
  SKIP 
END;

(* Returns the index of last 
   occurrence of the character "ch" in 
   the text "t", or -1 if "ch" does 
   not occur in "t". It is a 
   checked run-time error if "ch < 
   0" or "ch > 255". *)