type-predicates

Functions for checking types of values.

API

Most of these should be self-explanatory:

isString(thing)

isNumber(thing)

isInteger(thing)

isNumber(thing) && ((thing | 0) === (0 + thing))

isBoolean(thing)

isArray(thing)

isFunction(thing)

isNull(thing)

isNotNull(thing)

isObject(thing)

Use this to check for any non-null object, including arrays or wrapped primitives.

(typeof thing === 'object') && (thing !== null)

isPlainObject(thing)

Matches any non-null objects excluding arrays.

isObject(thing) && !Array.isArray(thing)

isPlainObjectStrict(thing)

As isPlainObject(thing), but also excludes wrapped primitives.

isDefined(thing)

isUndefined(thing)

exists(thing)

isNotNull(thing) && isDefined(thing)