Type Checking I also think the docs could be more clear about the precise definition of the required option. Let's start with looking at two different ways to test a computed property. That means when you're using in-DOM templates, camelCased prop names need to use their kebab-cased (hyphen-delimited) equivalents: Again, if you're using string templates, this limitation does not apply. Have a question about this project? By clicking “Sign up for GitHub”, you agree to our terms of service and 4. Already on GitHub? Hacktoberfest It is often used to test components that receive props from their parent component. `, Learn how component props work with a free lesson on Vue School. Component Registration Non-Prop Attributes There is no way to enforce a prop to be non-nully at all times without required: true and hence prop omission is disallowed. they're used to log you in. If you do console.log(this), you can see the context is simply the computed object: vue automatically binds props to this. For v3.x, click here. https://github.com/vuejs/vue/blob/dev/src/core/util/props.js#L94, 『 Vue小Case 』- Vue Prop中的 null vs undefined - 掘金. When prop validation fails, Vue will produce a console warning (if using the development build). It appears that it checks two things: I think in the case where a required prop has a default value, (1) should be relaxed. We use essential cookies to perform essential website functions, e.g. Fortunately, the class and style attributes are a little smarter, so both values are merged, making the final value: form-control date-picker-theme-dark. So far, you've seen props passed a static value, like in: You've also seen props assigned dynamically with v-bind or its shortcut, the : character, such as in: In the two examples above, we happen to pass string values, but any type of value can actually be passed to a prop. So for example, passing type="text" will replace type="date" and probably break it! data, computed, etc) will not be available inside default or validator functions. This means you should not attempt to mutate a prop inside a child component. So far, we’ve only seen props listed as an array of strings: Usually though, you’ll want every prop to be a specific type of value. We are not rendering the component with mount, though, so Vue isn't binding anything to this. In this case, it’s best to define a local data property that uses the prop as its initial value: The prop is passed in as a raw value that needs to be transformed. Tethering to a mobile hotspot is explicitly prohibited. Write for DigitalOcean Personally I'd go with adding nullable as a type declaration and using that as a flag, but I realize that's a little outside of the typical Vue approach. Millions of developers and companies build, ship, and maintain their software on GitHub — the largest and most advanced development platform in the world. -->, , , , // Basic type check (`null` and `undefined` values will pass any type validation), // Object or array defaults must be returned from, // The value must match one of these strings, // Unlike object or array default, this is not a factory function - this is a function to serve as a default value. Otherwise, how can I enforce a prop to never be null while also providing a default value if the prop value was not provided? If you want to pass all the properties of an object as props, you can use v-bind without an argument (v-bind instead of :prop-name). -->, , ,