Function validate

utils/ask.js:33–43

(value, state)

			initial,
			history,
			validate(value, state) {
				if (state && state.name === `command`) return true;
				if (state && state.name === `name`) {
					if (existsSync(value)) {
						return `Directory already exists: ./${value}`;
					} else {
						return true;
					}
				}
				return !value ? `Please add a value.` : true;
			}
		})
			.on(`cancel`, () => shouldCancel())
			.run();