function template

ftemplate.js

function tag(tagName) {
   return function() {
     var args = arguments;
     return function () {
       return '<' + tagName + '>' + evalContent(args) + '</' + tagName + '>';
     };
   }; 
}

function evalContent(args) {
  var result = "";
  for(var i = 0; i < args.length; i++) {
    if (typeof args[i] == "function") {
        result += args[i]();
    } else {
        result += args[i];
    }
  }
  return result;
}

var _div = tag('div');
var _h1 = tag('h1');
var _span = tag('span');

function index() {
   return _loop.index;
}

function _loop(start, count) {
   return function() {
      var args = arguments;
      return function() {
        var result = "";
        for (var i = start; i < count; i++) {
          _loop.index = i;
          result += evalContent(args);
        }
        return result;
      };
   };
}

var template = function(context) {
   return _loop(0,3)(
     _div(
       _h1(context.title), 
       _span(index)
     )
   );
};

var data = {
  title: 'test',
  arr: [1,2,3]
};


document.body.innerHTML = template(data)();