Macro intuitive::render

render!() { /* proc-macro */ }

Macro for rendering components.

Usage

This macro is used to render components from within Component::render. It uses a SwiftUI-like syntax, where the rough syntax is as follows:

render! { <component> }

component := <name> ( <parameters> ) { <children> }
children := <component> [ <component> ... ]

For example:

#[component(Root)]
fn render() -> AnyElement {
  render! {
    Section(title: "Hello, world!") {
      Text(text: "Here's a basic example of intuitive!")
    }
  }
}

is rendering a Section with a Text as its child.

Parameters

Parameters passed to components look like function arguments but are actually much closer to structure initialization. Like struct fields, they can be passed in any order, and they require the field name, unless the parameter and value are the same identifier. Unlike struct fields, you can omit parameters, as any omitted parameters are implicitly passed in with their default values.

Automatic Parameter Conversion

When passing parameters to components within a render! macro invocation, an implicit TryInto::try_into call is made for each parameter. This means that you can omit most .into() calls when passing parameters to components.

Children

Children to a component come after the component’s surrounded by braces ({ ... }). Like parameters, children are optional, but are only valid for components that accept them. For example Text accepts no children, but Section does.

Children are passed as Children, which have a fixed size. Components can therefore specify exactly how many children they take in. Some components, like VStack and HStack take in a variable number of children, while some, like Section accept a fixed number.