jridgewell/index.html

## index.html
<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8"/>
	<title>Directive Implementations: WeakMap vs Property vs Private Symbol</title>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
	<script src="./suite.js"></script>
</head>
<body>
	<h1>Open the console to view the results</h1>
	<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
</body>
</html>

## suite.js
"use strict";

(function (factory) {
	if (typeof Benchmark !== "undefined") {
		factory(Benchmark);
	} else {
		factory(require("benchmark"));
	}
})(function (Benchmark) {
	var suite = new Benchmark.Suite;

	Benchmark.prototype.setup = function () {
		let i = 0;

		const directives = new WeakMap();
		function directive(f) {
		    return (...args) => {
		        const d = f(...args);
		        directives.set(d, true);
		        return d;
		    };
		}
		const adderDirective = directive(x => {
		    return y => x + y;
		});

		function directiveProperty(f) {
		    return (...args) => {
		        const d = f(...args);
		        d.__isDirective = true;
		        return d;
		    };
		}
		const adderDirectiveProperty = directiveProperty(x => {
		    return y => x + y;
		});

		let sym;
		try {
		    sym = eval("%CreatePrivateSymbol('directive')");
		} catch {
		    throw new Error('reload v8 with --allow-natives-syntax');
		}
		function directivePrivateSymbol(f) {
		    return (...args) => {
		        const d = f(...args);
		        d[sym] = true;
		        return d;
		    };
		}
		const adderDirectivePrivateSymbol = directivePrivateSymbol(x => {
		    return y => x + y;
		});
	};


	suite.add("Using WeakMap", function () {
		// Using WeakMap
		i = 0;
		const add = adderDirective(1);
		if (directives.has(add)) {
		  i += add(2);
		}
	});

	suite.add("Using property", function () {
		// Using property
		i = 0;
		const add = adderDirectiveProperty(1);
		if (add.__isDirective) {
		  i += add(2);
		}
	});

	suite.add("Using Private Symbol", function () {
		// Using Private Symbol
		i = 0;
		const add = adderDirectivePrivateSymbol(1);
		if (add[sym]) {
		  i += add(2);
		}
	});

	suite.on("cycle", function (evt) {
		console.log(" - " + evt.target);
	});

	suite.on("complete", function (evt) {
		console.log(new Array(30).join("-"));

		var results = evt.currentTarget.sort(function (a, b) {
			return b.hz - a.hz;
		});

		results.forEach(function (item) {
			console.log((idx + 1) + ". " + item);
		});
	});

	console.log("Directive Implementations: WeakMap vs Property vs Private Symbol");
	console.log(new Array(30).join("-"));
	suite.run();
});
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8"/>
	<title>Directive Implementations: WeakMap vs Property vs Private Symbol</title>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/benchmark/1.0.0/benchmark.min.js"></script>
	<script src="./suite.js"></script>
	</head>
	<body>
	<h1>Open the console to view the results</h1>
	<h2><code>cmd + alt + j</code> or <code>ctrl + alt + j</code></h2>
	</body>
	</html>
	"use strict";

	(function (factory) {
	if (typeof Benchmark !== "undefined") {
	factory(Benchmark);
	} else {
	factory(require("benchmark"));
	}
	})(function (Benchmark) {
	var suite = new Benchmark.Suite;

	Benchmark.prototype.setup = function () {
	let i = 0;

	const directives = new WeakMap();
	function directive(f) {
	return (...args) => {
	const d = f(...args);
	directives.set(d, true);
	return d;
	};
	}
	const adderDirective = directive(x => {
	return y => x + y;
	});

	function directiveProperty(f) {
	return (...args) => {
	const d = f(...args);
	d.__isDirective = true;
	return d;
	};
	}
	const adderDirectiveProperty = directiveProperty(x => {
	return y => x + y;
	});

	let sym;
	try {
	sym = eval("%CreatePrivateSymbol('directive')");
	} catch {
	throw new Error('reload v8 with --allow-natives-syntax');
	}
	function directivePrivateSymbol(f) {
	return (...args) => {
	const d = f(...args);
	d[sym] = true;
	return d;
	};
	}
	const adderDirectivePrivateSymbol = directivePrivateSymbol(x => {
	return y => x + y;
	});
	};


	suite.add("Using WeakMap", function () {
	// Using WeakMap
	i = 0;
	const add = adderDirective(1);
	if (directives.has(add)) {
	i += add(2);
	}
	});

	suite.add("Using property", function () {
	// Using property
	i = 0;
	const add = adderDirectiveProperty(1);
	if (add.__isDirective) {
	i += add(2);
	}
	});

	suite.add("Using Private Symbol", function () {
	// Using Private Symbol
	i = 0;
	const add = adderDirectivePrivateSymbol(1);
	if (add[sym]) {
	i += add(2);
	}
	});

	suite.on("cycle", function (evt) {
	console.log(" - " + evt.target);
	});

	suite.on("complete", function (evt) {
	console.log(new Array(30).join("-"));

	var results = evt.currentTarget.sort(function (a, b) {
	return b.hz - a.hz;
	});

	results.forEach(function (item) {
	console.log((idx + 1) + ". " + item);
	});
	});

	console.log("Directive Implementations: WeakMap vs Property vs Private Symbol");
	console.log(new Array(30).join("-"));
	suite.run();
	});