@bemoje/parse-params

Parse function parameters and get their names, count, incl rest-parameters and default values.

install

npm install --save @bemoje/parse-params

usage

import parseParams from '@bemoje/parse-params'

parseParams(() => {})
//=> { name: '', count: 0, rest: false, params: [] }

parseParams(function someParsee(hello = 'world', num, ...palmTrees) {})
// => {
// 	name: 'someParsee',
// 	count: 3,
// 	rest: true,
// 	params: [
// 	  { arg: 0, name: 'hello', default: "'world'" },
// 	  { arg: 1, name: 'num', default: null },
// 	  { arg: 2, name: '...palmTrees', default: null }
// 	]
// }

Docs

/**
 * Parse function parameters and get their names, count, incl rest-parameters and default values.
 * @param {Function} fn - The function to parse
 * @returns {ParseResult} {name,count,rest,params:[...{arg,name,default}]}
 */
export function parseParams(fn: Function): ParseResult

export default parseParams

/**
 * @typedef {object} Param
 * @property {index} arg - The parameter index number
 * @property {string} name - The parameter name
 * @property {string} default - The default value. Not the value, but a string because it's just a parsed extract of the
 * function source code.
 */

/**
 * @typedef {object} ParseResult
 * @property {string} name - The function name
 * @property {integer} count - The total number of parameters excl. rest-parameters.
 * @property {boolean} rest - whether or not the last param is rest parameters.
 * @property {Array<Param>} params - Array with details about individual arguments
 */