node/tools/eslint/node_modules/onetime/readme.md
Rich Trott 4ffe804c81
tools: update ESLint to v4.0.0
Update ESLint and configuration to version 4.0.0.

Backport-PR-URL: https://github.com/nodejs/node/pull/14340
PR-URL: https://github.com/nodejs/node/pull/13645
Reviewed-By: Teddy Katz <teddy.katz@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Alexey Orlenko <eaglexrlnk@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
2017-07-18 14:45:47 -04:00

998 B

onetime Build Status

Ensure a function is only called once

When called multiple times it will return the return value from the first call.

Unlike the module once, this one isn't naughty extending Function.prototype.

Install

$ npm install --save onetime

Usage

let i = 0;

const foo = onetime(() => i++);

foo(); //=> 0
foo(); //=> 0
foo(); //=> 0
const foo = onetime(() => {}, {throw: true});

foo();

foo();
//=> Error: Function `foo` can only be called once

API

onetime(fn, [options])

Returns a function that only calls fn once.

fn

Type: Function

Function that should only be called once.

options

Type: Object

throw

Type: boolean
Default: false

Throw an error when called more than once.

License

MIT © Sindre Sorhus