Get arguments of a function, useful for and used in dependency injectors. Works for regular functions, generator functions and arrow functions.

Install with npm

$ npm i function-arguments --save

For more use-cases see the tests

const functionArguments = require('function-arguments')

Get function arguments names.

Params

• fn {Function}: Function from which to get arguments names.
• returns {Array}

Example

var fnArgs = require('function-arguments')

console.log(fnArgs(function (a, b, c) {})) // => [ 'a', 'b', 'c' ]
console.log(fnArgs(function named (a , b, c) {})) // => [ 'a', 'b', 'c' ]

console.log(fnArgs(a => {})) // => [ 'a' ]
console.log(fnArgs((a, b) => {})) // => [ 'a', 'b' ]

console.log(fnArgs(function * (a ,b, c) {})) // => [ 'a', 'b', 'c' ]
console.log(fnArgs(function * named (a ,b, c) {})) // => [ 'a', 'b', 'c' ]

As it works for ES2015, it also works if you use comments in weird places.

console.log(fnArgs(function /* something may */ (
  // go,
  go,
  /* wrong, */
  here
  // (when, using, comments) {}
) { return 1 })) // => [ 'go', 'here' ]

• flatten-arguments: Fastest, simplest and smallest. Pass arguments object or list of… more | homepage
• fn-args: Get the arguments of a function | homepage
• fn-name: Get the name of a named function | homepage
• get-fn-name: Get function name with strictness and correctness in mind. Also… more | homepage
• handle-arguments: Get separately non-callback arguments in .arguments and the last argument… more | homepage
• manage-arguments: Prevents arguments leakage - managing arguments. From Optimization killers by… more | homepage
• parse-function: Parse a function, arrow function or string to object with… more | homepage

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
But before doing anything, please read the CONTRIBUTING.md guidelines.