Implementation

index.js

@@ -0,0 +1,21 @@
+'use strict';
+
+var boolToStr = Boolean.prototype.toString;
+
+var tryBooleanObject = function tryBooleanObject(value) {
+	try {
+		boolToStr.call(value);
+		return true;
+	} catch (e) {
+		return false;
+	}
+};
+var toStr = Object.prototype.toString;
+var boolClass = '[object Boolean]';
+var hasToStringTag = typeof Symbol === 'function' && typeof Symbol.toStringTag === 'symbol';
+
+module.exports = function isBoolean(value) {
+	if (typeof value === 'boolean') { return true; }
+	if (typeof value !== 'object') { return false; }
+	return hasToStringTag ? tryBooleanObject(value) : toStr.call(value) === boolClass;
+};