compare block helper for handlebars

gistfile1.js

	// {{compare unicorns ponies operator="<"}}
	// 	I knew it, unicorns are just low-quality ponies!
	// {{/compare}}
	// 
	// (defaults to == if operator omitted)
	//
	// {{equal unicorns ponies }}
	// 	That's amazing, unicorns are actually undercover ponies
	// {{/equal}}
	// (from http://doginthehat.com.au/2012/02/comparison-block-helper-for-handlebars-templates/)

	Handlebars.registerHelper('compare', function(lvalue, rvalue, options) {

		if (arguments.length < 3)
			throw new Error("Handlerbars Helper 'compare' needs 2 parameters");

		operator = options.hash.operator || "==";
		
		var operators = {
			'==':		function(l,r) { return l == r; },
			'===':	function(l,r) { return l === r; },
			'!=':		function(l,r) { return l != r; },
			'<':		function(l,r) { return l < r; },
			'>':		function(l,r) { return l > r; },
			'<=':		function(l,r) { return l <= r; },
			'>=':		function(l,r) { return l >= r; },
			'typeof':	function(l,r) { return typeof l == r; }
		}

		if (!operators[operator])
			throw new Error("Handlerbars Helper 'compare' doesn't know the operator "+operator);

		var result = operators[operator](lvalue,rvalue);

		if( result ) {
			return options.fn(this);
		} else {
			return options.inverse(this);
		}
		
	});