isBoolean

isBoolean :: a β†’ Boolean

Evaluates whether the given value is of type Boolean

import isBoolean from 'deep-waters/isBoolean';

isBoolean(true); // β†’ true
isBoolean(false); // β†’ true
isBoolean(new Boolean(true)); // β†’ true

isBigInt(20); // β†’ false
isBigInt("hello"); // β†’ false
isBigInt(undefined"); // β†’ false

isBoolean, like any other type validator, is mostly used in composed validators:

import isString from 'deep-waters/isString';
import matchesPattern from 'deep-waters/matchesPattern';

const isEmail = compose(
  isString,
  matchesPattern(/^\w+([.-]?\w+)*@\w+([.-]?\w+)*(\.\w{2,3})+$/),
);

isBoolean is built on top of ofClass validator and rely on Object.prototype.toString to check on the received value type in order to avoid typeof weird behaviours and encouraging a runtime strict type validation.

Last updated