#!/usr/local/bin/jsish -u %s

var str = "abcdefgh";

var n = 2;
var m = 3;

// In jsish, semi-colon first character lines are echoed with result
;str;
;n;
;m;

//  *  starting from n characters in and of m length;
;str.substr(n, m);

//  * starting from n characters in, up to the end of the string;
;str.substr(n);
;str.substring(n);

//  * whole string minus last character;
;str.substring(0, str.length - 1);

//  * starting from a known character within the string and of m length;
;str.substr(str.indexOf('b'), m);

//  * starting from a known substring within the string and of m length.
;str.substr(str.indexOf('bc'), m);


/* Functional */
var res = (function () {
    'use strict';

    //  take :: Int -> Text -> Text
    function take(n, s) {
        return s.substr(0, n);
    }

    //  drop :: Int -> Text -> Text
    function drop(n, s) {
        return s.substr(n);
    }


    // init :: Text -> Text
    function init(s) {
        var n = s.length;
        return (n > 0 ? s.substr(0, n - 1) : undefined);
    }

    // breakOn :: Text -> Text -> (Text, Text)
    function breakOn(strPattern, s) {
        var i = s.indexOf(strPattern);
        return i === -1 ? [strPattern, ''] : [s.substr(0, i), s.substr(i)];
    }


    var str = 'abcdefgh';


    return JSON.stringify({

        'from 4 in, of 3 length': (function (n, m) {
            return take(m, drop(n, str));
        })(4, 3),


        'from 3 in, up to end' : (function (n) {
            return drop(n, str);
        })(3),


        'all but last' : init(str),


        'from matching b, of length 3' : (function (pattern, s, n) {
            return take(n, breakOn(pattern, s)[1]);
        })('b', str, 3),


        'from matching bc, of length 4':(function (pattern, s, n) {
            return take(n, breakOn(pattern, s)[1]);
        })('bc', str, 4)

    }, true);

})();
;res;