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
.
$ npm install --save onetime
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
Returns a function that only calls fn
once.
Type: Function
Function that should only be called once.
Type: Object
Type: boolean
Default: false
Throw an error when called more than once.
MIT © Sindre Sorhus