libs/lodash.js
function padLeft(string, length, chars) {
      string = string == null ? '' : String(string);
      return createPad(string, length, chars) + string;
    }
function padLeft(string, length, chars) {
      string = string == null ? '' : String(string);
      return createPad(string, length, chars) + string;
    }
function padLeft ( string , length , chars ) { string = string == null ? '' : String ( string ) ; return createPad ( string , length , chars ) + string ; }
Pads `string` on the left side if it is shorter then the given padding
length. The `chars` string may be truncated if the number of padding
characters exceeds the padding length.

@static
@memberOf _
@category Strings
@param {string} [string=''] The string to pad.
@param {number} [length=0] The padding length.
@param {string} [chars=' '] The string used as padding.
@returns {string} Returns the padded string.
@example

_.padLeft('abc', 6);
// => '   abc'

_.padLeft('abc', 6, '_-');
// => '_-_abc'

_.padLeft('abc', 3);
// => 'abc'
Pads string on the left side if it is shorter then the given padding length . The chars string may be truncated if the number of padding characters exceeds the padding length .