each_with_index handlebars helper, adds an {{index}} prop accessible from within the block

each_with_index.js

// <ul data-length="{{records.length}}">
// {{#each_with_index records}}
// 	<li class="legend_item{{this.index}}" z-index="{{this.reverse}}"><span></span>{{this.name}}</li>
// {{/each_with_index}}
// </ul>

Handlebars.registerHelper("each_with_index", function(array, options) {
	var buffer = "";
	for (var i = 0, j = array.length; i < j; i++) {
		var item = array[i];

		// stick an index property onto the item, starting with 1, may make configurable later
		item.index = i+1;
		item.reverse = j-i;

		// show the inside of the block
		buffer += options.fn(item);
	}

	// return the finished buffer
	return buffer;

});