because i don't like string concatination

native-string-templates.js

/**
 * string parser with data passed as arguments
 *
 * @param {arguments}
 * @return {string}
 *
 * example: 
 * --------
 * 'i used both [0] & [1], however [1] looks good so far'.parse( 'iphone', 'andoird' );         // "i used both iphone & andoird, however andoird looks good so far"
 * 'the weather now in [0] seems to be [1]'.parse( 'Dubai', function() { return 'very hot'; }); // "the weather now in Dubai seems to be very hot"
 */

String.prototype.parse = function() {
  var args = arguments;
  return this.replace( /\[([0-9]+)\]/g, function( token, match ) {
    var index = parseInt( match, 10 );
    var data = args[ index ];
    return isNaN( index ) || data == null ? token: ( typeof data !== 'function' ? data: data() );
  });
}


/**
 * string parser with data passed as an object literal
 *
 * @param {object} data
 * @return {string}
 *
 * example: 
 * --------
 * 'i used both {mob1} & {mob2}, however {mob2} looks good so far'.tmpl({ mob1: 'iphone', mob2: 'andoird' });         // "i used both iphone & andoird, however andoird looks good so far"
 * 'the weather now in {city} seems to be {temp}'.tmpl({ city: 'Dubai', temp: function() { return 'very hot'; } });   // "the weather now in Dubai seems to be very hot"
 */

String.prototype.tmpl = function( data ) {
  return this.replace( /{([A-Za-z0-9_$\-]+)}/g, function ( token, match ) {
    return ( typeof data[ match ] !== 'function' ) ? data[ match ] : data[ match ]();
  });
}

non-native-templates.js

/**
 *  in case you don't like extending native objects
 */

/**
 * tiny string parser
 *
 * @param {string} str
 * @param {arguments}
 * @return {string}
 *
 * example: 
 * --------
 * parse( 'i used both [0] & [1], however [1] looks good so far', 'iphone', 'andoird' );         // "i used both iphone & andoird, however andoird looks good so far"
 * parse( 'the weather now in [0] seems to be [1]', 'Dubai', function() { return 'very hot'; }); // "the weather now in Dubai seems to be very hot"
 */

function parse( str ) {
  var args = Array.prototype.slice.call( arguments, 1 );
  return str.replace( /\[([0-9]+)\]/g, function( token, match ) {
    var index = parseInt( match, 10 );
    var data = args[ index ];
    return isNaN( index ) || data == null ? token: ( typeof data !== 'function' ? data: data() );
  });
}


/**
 * template
 *
 * @param {string} str
 * @param {object} data
 * @return {string}
 *
 * example: 
 * --------
 * tmpl( 'i used both {mob1} & {mob2}, however {mob2} looks good so far', { mob1: 'iphone', mob2: 'andoird' });         // "i used both iphone & andoird, however andoird looks good so far"
 * tmpl( 'the weather now in {city} seems to be {temp}', { city: 'Dubai', temp: function() { return 'very hot'; } });   // "the weather now in Dubai seems to be very hot"
 */

function tmpl( str, data ) {
  return str.replace( /{([A-Za-z0-9_$\-]+)}/g, function ( token, match ) {
    return ( typeof data[ match ] == 'function' ) ? data[ match ]() : data[ match ];
  });
}