diff --git a/packages/babel-helper-get-function-arity/README.md b/packages/babel-helper-get-function-arity/README.md index 1058da9e1e..d341c9ce35 100644 --- a/packages/babel-helper-get-function-arity/README.md +++ b/packages/babel-helper-get-function-arity/README.md @@ -1,5 +1,21 @@ # @babel/helper-get-function-arity +Function that returns the number of arguments that a function takes. +* Examples of what is considered an argument can be found at [MDN Web Docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/length) + ## Usage -TODO +```javascript +import getFunctionArity from "@babel/helper-get-function-arity"; + +function wrap(state, method, id, scope) { + // ... + if (!t.isFunction(method)) { + return false; + } + + const argumentsLength = getFunctionArity(method); + + // ... +} +```