isnot

isnot

Type checking package for JavaScript, include just once in your entrypoint like

you need to fetch every single function like const {isString} = require('isnot');

Available functions

Strings

isString('') //true

isNotString(()=>{}) //true

isStringAndNotEmpty('') //false

isStringAndNotEmpty(' ') //false

isStringAndNotEmpty('hey') //true

isEmptyString({}) //false

isEmptyString('') //true

isNotEmptyString('') //false

isEmail('a@b.c') //true

isNotEmail('whatever@domain') //true

isVariableName('var') //true (technically not, but it can be a property of an object accessed without ['...'])

isVariableName('oh dear') //false

isVariableName('0rel') //false cannot start with number

isVariableName('var0') //true

isNotVariableName('a@a') //true

Arrays

isArray([]) // true

isArray({}) // false

isEmptyArray([]) // true

isEmptyArray({}) // false

isNotEmptyArray([]) // false

isNotEmptyArray([1]) // true

isNotEmptyArray({}) // false

Objects

isObject([]) // FALSE, arrays are not objects for this library

isObject({}) // true

isNotObject('') //true

isEmptyObject([]) //false

isNotEmptyObject({a: 1}) //true

Numbers

isNumber(1) //true

isNotNumber(NaN) //true

isInt(0) //true

isNotInt(1.2) //true

Bool

isBool(1) //false

isNotBool(NaN) //true

isBool(0) //false

isBool(true) //true

Generic

isEmpty([]) //true

isEmpty('') //true

isEmpty(' ') //true

isEmpty({}) //true

isEmpty(null) //true

isEmpty(undefined) //true

isEmpty(0) //false

isNotEmpty('hey') //true

Dates

isDate('') //false

isNotDate('') //true

isDate(new Date()) //true

isDate('1970-01-01T00:00:00.000Z') //true

isDate('1970-01-01T00:00:00') //true

isDate('1970-01-01T00:00') //true

isDate('1970-01-01') //true

isDate('0000-00-00') //false

isDate('1970-13-01') //false (bad month)

isDate('1970-01-32') //false (bad day)

isDate('2017-02-29') //false (not leap year)

undefined

isUndefined('') //false

isUndefined(false) //false

isUndefined(undefined) //true

isUndefined(typeof undefined) //false

isUndefined({}.inventedProp) //true