onetime

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

```js let i = 0;

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

foo(); //=> 0 foo(); //=> 0 foo(); //=> 0 ```

```js 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.