REBOL [ File: %substring.r Date: 3-Febr-2004 Title: "Simple substring function - returns empty when outside boundery" Purpose: "Working around string series" Author: "Hein Hoenjet" library: [ level: 'beginner platform: 'all type: [tutorial tool] domain: [text text-processing] tested-under: none support: none license: none see-also: none ] ] substring: function [ { Expression function to get a substring from a string Usage: substring "abcdefghijk" 4 9 } s [series!] {String} f [number!] {Position from} t [number!] {Position until, -1 when end of series} ] [ ] [ (if t = -1 [ t: length? s]) return skip (copy/part s t) (f - 1) ]