code: function issorted( arr, clbk ) {
  	if ( !Array.isArray( arr ) ) {
  		throw new TypeError( 'issorted()::invalid input argument. Must provide an array.' );
  	}
  	if ( arguments.length > 1 ) {
  		if ( typeof clbk !== 'function' ) {
  			throw new TypeError( 'issorted()::invalid input argument. Comparator must be a function.' );
  		}
  	}
  	var len = arr.length,
  		i;
  	if ( !clbk ) {
  		// Default: ascending order...
  		for ( i = 0; i < len-1; i++ ) {
  			if ( arr[ i ] > arr[ i+1 ] ) {
  				return false;
  			}
  		}
  		return true;
  	}
  	// Impose arbitrary sort order...
  	for ( i = 0; i < len-1; i++ ) {
  		if ( clbk( arr[i], arr[i+1] ) > 0 ) {
  			return false;
  		}
  	}
  	return true;
  }
docs: ISSORTED // 
  FUNCTION: issorted( arr[, comparator] )
  Returns a boolean indicating if an input array is sorted.
  
  @param {Array} arr - input array
  @param {Function} [comparator] - comparator function invoked for each pair of consecutive elements which returns a numeric value indicating if elements are ordered
  @returns {Boolean} boolean indicating if array is sorted