_.isFunction(value)

_.isFunction(value)

_.isFunction(_);
// => true
 
_.isFunction(/abc/);
// => false

import baseGetTag from './.internal/baseGetTag.js'
import isObject from './isObject.js'

/**
 * Checks if `value` is classified as a `Function` object.
 *
 * @since 0.1.0
 * @category Lang
 * @param {*} value The value to check.
 * @returns {boolean} Returns `true` if `value` is a function, else `false`.
 * @example
 *
 * isFunction(_)
 * // => true
 *
 * isFunction(/abc/)
 * // => false
 */
//判断一个值是否是一个function对象
function isFunction(value) {
  if (!isObject(value)) {//先判断value是否是对象
    return false
  }
  // The use of `Object#toString` avoids issues with the `typeof` operator
  // in Safari 9 which returns 'object' for typed arrays and other constructors.
  const tag = baseGetTag(value)//获取value的toStringTag
  return tag == '[object Function]' || tag == '[object AsyncFunction]' ||
    tag == '[object GeneratorFunction]' || tag == '[object Proxy]'
    //value的toStringTag等于[object Function]或者[object AsyncFunction]或者[object GeneratorFunction]或者[object Proxy]
}

export default isFunction