call-once-fn

Wraps a function so it runs only on its first call.

Install

npm install call-once-fn

Use

Save this as example.cjs and run node example.cjs:

var assert = require('assert');
var once = require('call-once-fn');

var results = [];
var callback = once(function () {
  results.push(Array.prototype.slice.call(arguments));
});

callback('error', 'value1', 'value2');
callback('ignored');

assert.deepEqual(results, [['error', 'value1', 'value2']]);
console.log(results[0]);

The first call forwards all arguments and returns the wrapped function's result. Later calls return undefined without calling the wrapped function.

License

MIT