How to use the typechecker.isMap function in typechecker

for (var key = 0; key < subject.length; ++key) {
			var value = subject[key];
			if (callback.call(subject, value, key, subject) === false) {
				break;
			}
		}
	} else if (typeChecker.isPlainObject(subject)) {
		for (var _key in subject) {
			if (subject.hasOwnProperty(_key)) {
				var _value = subject[_key];
				if (callback.call(subject, _value, _key, subject) === false) {
					break;
				}
			}
		}
	} else if (typeChecker.isMap(subject)) {
		var entries = subject.entries();
		var entry = void 0;while (entry = entries.next().value) {
			var _entry = entry;

			var _entry2 = _slicedToArray(_entry, 2);

			var _key2 = _entry2[0];
			var _value2 = _entry2[1]; // destructuring

			if (callback.call(subject, _value2, _key2, subject) === false) {
				break;
			}
		}
	} else {
		// Perhaps falling back to a `for of` loop here would be sensible
		throw new Error('eachr does not know how to iterate what was passed to it');

if ( callback.call(subject, value, key, subject) === false ) {
				break
			}
		}
	}
	else if ( typeChecker.isPlainObject(subject) ) {
		for ( const key in subject ) {
			if ( subject.hasOwnProperty(key) ) {
				const value = subject[key]
				if ( callback.call(subject, value, key, subject) === false ) {
					break
				}
			}
		}
	}
	else if ( typeChecker.isMap(subject) ) {
		const entries = subject.entries()
		let entry; while ( entry = entries.next().value ) {
			const [key, value] = entry  // destructuring
			if ( callback.call(subject, value, key, subject) === false ) {
				break
			}
		}
	}
	else {
		// Perhaps falling back to a `for of` loop here would be sensible
		throw new Error('eachr does not know how to iterate what was passed to it')
	}

	// Return
	return subject
}