README.md

fast-format

This is a string formatter like util.format() method in Node.js, supports just only %s placeholder but accordingly faster than that. It will be one of the best solution if need a speed rather than complex formatting.

Usage

Same as util.format() method.

format(formatString[, ...])

If use one formatting repeatedly, recommended to compile the formatString in advance.

format.compile(formatString)

Example

let s = format('%s, %s!', 'Hello', 'world');
console.log(s);     // => 'Hello, world!'

let f = format.compile('%s, %s!');
let s1 = f('Hello', 'world');
console.log(s1);    // => 'Hello, world!'
let s2 = f('Howdy', 'World');
console.log(s2);    // => 'Howdy, World!'

Benchmark

// Bench 1
let s = Date.now();
for (let i = 0, len = 100000000; i < len; i++) {
    format('i = %s, len = %s', i, len);
}
console.log(Date.now() - s);

// Bench 2
let s = Date.now();
let f = format.compile('i = %s, len = %s');
for (let i = 0, len = 100000000; i < len; i++) {
    f(i, len);
}
console.log(Date.now() - s);

environment1: Core i7 2.2GHz + Node.js v6.9.5

module	time	bench
fast-format	12,388 msec	2
fast-format	22,039 msec	1
util.format	28,659 msec	1

---

environment2: Core i7 2.2GHz + Google Chrome 56.0.2924.87

module	time	bench
fast-format	12,898 msec	2
fast-format	22,705 msec	1
util.format	99,103 msec	1

The util.format() method was converted with Browserify to run on the browser.

Installation

via npm

npm install fast-format --save

via Bower

bower install fast-format

directly (in case of the browser)

<script src="/path/to/fast-format.min.js"></script>

Browser Support

Google Chrome, Firefox, Safari, Opera, Microsoft Edge and IE 6+

License

MIT