joinForEach

gistfile1.js

Array.prototype.joinForEach = function(separator, fn, scope){
  var array = new Array();

    for (var i = 0, len = this.length; i < len; ++i) {
        fn.call(scope, array, this[i], i, this);
    }

	return array.join(separator);
};

var r, a = [{ name: 'Banana', url: '/Banana'}, { name: 'Abacaxi', url: '/Abacaxi'}, { name: 'Pera', url: '/Pera'}, { name: 'Tomate', url: '/Tomate'}];

r = a.joinForEach(', ', function(arr, item){
	arr.push('<a href="'+ item.url +'">'+ item.name +'</a>');
});

console.log( r ); // "<a href="/Banana">Banana</a>, <a href="/Abacaxi">Abacaxi</a>, <a href="/Pera">Pera</a>, <a href="/Tomate">Tomate</a>"