is-of-type
v1.2.3
Published
Various utility functions such as isNonEmptyString, isNumber, isNull, isDefined etc.
Downloads
53
Maintainers
Readme
is-of-type
A collection of utility functions to help deal with JavaScript’s built-in types and add readability to your code. Only ~430 bytes
when minified and gzipped.
Install
`npm install is-of-type --save`
# or
`yarn add is-of-type`
Usage
All of the functions exports by this package have the following signature: fn(arg: Any): boolean
.
This package helps you turn:
if (x !== null && x !== undefined) {
//...
}
if (typeof fn === 'function') {
fn();
}
if (typeof n === 'number' && !isNaN(n)) {
// ...
}
if (typeof s === 'string' && s.length > 0) {
// ...
}
if (typeof o === 'object') {
// ...
}
into
import {
isDefinedAndNotNull,
isFunction,
isNumberAndNotNaN,
isNonEmptyString,
isObject,
} from 'is-of-type';
if (isDefinedAndNotNull(x)) {
//...
}
if (isFunction(fn)) {
fn();
}
if (isNumberAndNotNaN(n)) {
// ...
}
if (isNonEmptyString(s)) {
// ...
}
if (isObject(o)) {
/*
* Identical to typeof o === 'object', so let’s null, Array, Set, Map etc. pass
* You can compose your own method to improve this, e.g:
* const isRealObject = (o) => {
* return isObjecy(o) && !isNull(o);
* }
*/
}
And many other checks that are easier to read and composable.
List of Functions
This package exports the following utilities:
isDefined
(orisDef
)isNull
isDefinedAndNotNull
isDefAndNotNull
isArray
isNonEmptyArray
isBoolean
(orisBool
)isFunction
(orisFn
)isObject
- Strict check
typeof o === object'
- So returns true for
Array
,null
,Set
,Map
,Date
, andregex
.
- Strict check
isDate
isString
isNonEmptyString
isNumber
isNaN
isNumberAndNotNaN