isRegExp

isRegExp :: a β†’ Boolean

Evaluates whether the given value is of type RegExp

import isRegExp from 'deep-waters/isRegExp';

isRegExp(/^foo$/); // β†’ true
isRegExp(new RegExp(/^foo$/)); // β†’ true

isRegExp("/^foo$/"]); // β†’ false
isRegExp(null); // β†’ false
isRegExp("foo"); // β†’ false

isRegExp, 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})+$/),
);

isRegExp 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.

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