determine if the target meets the type condition
A type condition, see TypeCondition
with string
is('xxx', 'string') // => truewith constructor
const p = new Promise()
is(p, Promise) // => truewith regexp
const $a = document.querySelector('a')
const $h1 = document.querySelector('h1')
is($a, /Element/) // => true
is($h1, /Element/) // => trueyou can provide an array of type condition, return true if any of them are met
array of condition
is(new Set([1, 2]), [Map, Set]) // => truedetermine if the target is an array
isArray([]) // => true
isArray({ 0: 1, length: 1 }, true) // => trueyou can provide secound params to check target if arraylike
return true if target likes an array
determine if the target is an array like object. this function is alias of isArray(target, true)
isArrayLike([]) // => true
isArrayLike({ 0:1, length: 1 }) // => truedetemine if target can be cloned, for example: jQuery Object
detemine if target is a decimal. notice any type which is not number type will return false
isDec(1) // => false
isDec(1.1) // => truedetermine the target is empty, it's very useful in form validation the followings mean target is empty
isEmpty({}) // => true
isEmpty(['']) // => false
isEmpty('xxx') // => false
isEmpty(true) // => false
isEmpty('') => truecompare target with other and determine if they are equal
isEqual(1, 1) // => true
isEqual(1, new Number(1)) // => true
isEqual({a: 1}, {a: 1}) // => true
isEqual(1, '1') // => falsedetemine if target is a global object, for example: window, global
detemine if target is greater than other notice any type which is not number type will return false
isGt(2, 1) // => true
isGt(1, 2) // => false
isGt('0', 1) // => falsedetemine if target is a integer. notice any type which is not number type will return false
isInt(1) // => true
isInt(1.1) // => falsedetemine if target is iterable it's very useful to check a object before for..of
let arr = [1, 2]
let map = new Map([1, 2])
isIterable(arr) // => true
isIterable(map) // => true
for (item of arr) {
//...
}
for (item of map) {
//...
}
detemine if target is less than other notice any type which is not number type will return false
isLt(1, 2) // => true
isLt('0', 1) // => falsedetemine if target is a negative number. notice any type which is not number type will return false
isNegative(-1) // => true
isNegative(1) // => falsealso work between 0 and -0
isNegative(-0) // => true
isNegative(0) // => falsedetemine if target is object-like such as function
isObjectLike({}) // => true
isObjectLike(function() {}) // => trueit usually use to check some variable is extendable
`javascript
let namespace = {}
if (isObjectLike(namespace)) {
namespace.member = 1
}
`
detemine if target is a plain object
isPlainObject({ a: 1 }) // => true
isPlainObject(new Promise(() => {})) // falsedetemine if target is a positive number. notice any type which is not number type will return false
isPositive(-1) // => false
isPositive(1) // => truealso work between 0 and -0
isPositive(-0) // => false
isPositive(0) // => truedetemine if target is primitive type, such as 1, "foobar"
isPrimitive(1) // => true
isPrimitive(null) // => true
isPrimitive({}) // => false
detemine if target is a thenable. it can be easily combined with asynchronous methods
you can checkout what is thenable here
if (isThenable(obj)) {
obj.then(callback)
}
async foo() {
if (isThenable(obj)) {
await obj
}
}determine if the target is an typed array, like Uint8Array, Int8Array
isTypedArray(new Uint8Array(16)) // => true
isTypedArray([]) // => falsedetemine if target is a number but NaN.
isValidNumber('string') // => false
isValidNumber(new Number(11)) // => true
isValidNumber(11) // => false
isValidNumber('11') // => falsereturn type of target. the return value will follow the following rules.
type('string') // => 'string'
type(1) // => 'number'
type(null) // => 'null'
type(undefined) // => 'undefined'
type(new Set([1, 2, 3])) // => 'Set'
type(new Number(111)) // => 'Number'
with boxed only
type(1, true) // => 'Number'
type(null, true) // => 'Null'boxedOnly means return will always return boxed constructor name if target is primitive
Generated using TypeDoc
a condition for is function
is(promise, Promise)just simply equalpromise instanceof Promise