SOURCE CODE: Uize.Str.CharClass (view docs)

/*______________
|       ______  |   U I Z E    J A V A S C R I P T    F R A M E W O R K
|     /      /  |   ---------------------------------------------------
|    /    O /   |    MODULE : Uize.Str.CharClass Class
|   /    / /    |
|  /    / /  /| |    ONLINE : http://www.uize.com
| /____/ /__/_| | COPYRIGHT : (c)2014-2016 UIZE
|          /___ |   LICENSE : Available under MIT License or GNU General Public License
|_______________|             http://www.uize.com/license.html
*/

/* Module Meta Data
  type: Class
  importance: 1
  codeCompleteness: 100
  docCompleteness: 100
*/

/*?
  Introduction
    The =Uize.Str.CharClass= module defines a simple class that provides methods for working with strings that may contain chars of a specific character class.

    *DEVELOPERS:* `Chris van Rensburg`
*/

Uize.module ({
  name:'Uize.Str.CharClass',
  superclass:'Uize.Oop.BasicClass',
  builder:function (_superclass) {
    'use strict';

    var
      /*** Variables for Scruncher Optimization ***/
        _true = true,
        _false = false,

      /*** General Variables ***/
        _trueFlag = {}
    ;

    /*** Private Instance Methods ***/
      function _indexOfClassCharOrNon (m,_sourceStr,_isClassChar,_direction,_startPos) {
        var
          _charsLookup = m._charsLookup,
          _sourceStrLength = _sourceStr.length
        ;
        if (_sourceStrLength) {
          _startPos = _startPos != undefined ? _startPos : -_direction * Infinity;
          var _endPos = _direction == 1 ? _sourceStrLength : -1;
          if ((_startPos - _endPos) * _direction < 0) {
            if (_sourceStrLength == 1) {
              return (_charsLookup [_sourceStr] == _trueFlag) == _isClassChar ? 0 : -1;
            } else {
              for (
                var _charNo = _direction == 1
                  ? Math.max (_startPos,0) - 1
                  : Math.min (_startPos,_sourceStrLength - 1) + 1
                ;
                (_charNo += _direction) != _endPos;
              )
                if ((_charsLookup [_sourceStr.charAt (_charNo)] == _trueFlag) == _isClassChar)
                  return _charNo
              ;
            }
          }
        }
        return -1;
      }

    return _superclass.subclass ({
      constructor:Uize.noNew (function (_chars) {this.setChars (_chars)}),

      instanceMethods:{
        setChars:function (_chars) {
          this._charsLookup = _chars
            ? Uize.lookup (
              Uize.map (
                _chars,
                function (_char) {return typeof _char == 'string' ? _char : String.fromCharCode (+_char)}
              ),
              _trueFlag
            )
            : {}
          ;
        },

        isClassChars:function (_sourceStr) {
          return !!_sourceStr && _indexOfClassCharOrNon (this,_sourceStr,_false,-1) == -1;
        },

        isNonClassChars:function (_sourceStr) {
          return !!_sourceStr && _indexOfClassCharOrNon (this,_sourceStr,_true,-1) == -1;
        },

        hasClassChars:function (_sourceStr) {
          return !!_sourceStr && _indexOfClassCharOrNon (this,_sourceStr,_true,-1) > -1;
        },

        hasNonClassChars:function (_sourceStr) {
          return !!_sourceStr && _indexOfClassCharOrNon (this,_sourceStr,_false,-1) > -1;
        },

        indexOfClassChar:function (_sourceStr,_startPos) {
          return _indexOfClassCharOrNon (this,_sourceStr,_true,1,_startPos);
        },

        lastIndexOfClassChar:function (_sourceStr,_startPos) {
          return _indexOfClassCharOrNon (this,_sourceStr,_true,-1,_startPos);
        },

        indexOfNonClassChar:function (_sourceStr,_startPos) {
          return _indexOfClassCharOrNon (this,_sourceStr,_false,1,_startPos);
        },

        lastIndexOfNonClassChar:function (_sourceStr,_startPos) {
          return _indexOfClassCharOrNon (this,_sourceStr,_false,-1,_startPos);
        }
      }
    });
  }
});