type check

# Node.js

function typeOf(obj) {
  return {}.toString.call(obj).split(" ")[1].slice(0, -1).toLowerCase();
}

const values = [
  true,
  10,
  "foo",
  Symbol("bar"),
  null,
  undefined,
  NaN,
  {},
  [],
  function () {},
  new Error(),
  new Date(),
  /a/,
  new Map(),
  new Set(),
  Promise.resolve(),
  function* () {},
  class {},
];

for (value of values) {
  console.log(typeOf(value));
}

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Output

boolean
number
string
symbol
null
undefined
number
object
array
function
error
date
regexp
map
set
promise
generatorfunction
function

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# Go

package main

import (
	"fmt"
	"reflect"
	"regexp"
	"time"
)

func main() {
	values := []interface{}{
		true,
		int8(10),
		int16(10),
		int32(10),
		int64(10),
		uint(10),
		uint8(10),
		uint16(10),
		uint32(10),
		uint64(10),
		uintptr(10),
		float32(10.5),
		float64(10.5),
		complex64(-1 + 10i),
		complex128(-1 + 10i),
		"foo",
		byte(10),
		'a',
		rune('a'),
		struct{}{},
		[]string{},
		map[string]int{},
		func() {},
		make(chan bool),
		nil,
		new(int),
		time.Now(),
		regexp.MustCompile(`^a$`),
	}

	for _, value := range values {
		fmt.Println(reflect.TypeOf(value))
	}
}

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Output

bool
int8
int16
int32
int64
uint
uint8
uint16
uint32
uint64
uintptr
float32
float64
complex64
complex128
string
uint8
int32
int32
struct {}
[]string
map[string]int
func()
chan bool
<nil>
*int
time.Time
*regexp.Regexp

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编辑

#Go #Node.js

上次更新: 2022/09/30, 11:34:22

← types if/else→