Fix the types of Component's render function #1085
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src/preact.d.ts
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| function h<P>( | ||
| node: ComponentFactory<P>, | ||
| params: Attributes & P | null, | ||
| ...children: (ComponentChild | ComponentChildren)[] |
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ComponentChildren = ComponentChild[]
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Actually preact also accepts an array of ComponentChildren as a valid argument to h()
example
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But If I understand correctly your example your are passing a ComponentChild[] (which is an alias for ComponentChildren), not a ComponentChildren[] (that would mean ComponentChild[][]).
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I'm indeed passing a ComponentChildren[] because children is a rest parameter.
Take this example and feed it the typescript compiler:
type SomeArrayType = string[];
function test(...test: SomeArrayType) {}
test(['a', 'b', 'c']);e.g. here in the typescript playground.
And you'll get the error/warning: Argument of type 'string[]' is not assignable to parameter of type 'string'.
If you change the function signature to (...test: SomeArrayType[]) the error/warning will disapear.
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Huh, it appears Preact does support ComponentChild[][] and flattens it to a single list of children: example
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ACK! Removed the corresponding commit
| @@ -98,18 +98,18 @@ declare namespace preact { | |||
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| forceUpdate(callback?: () => void): void; | |||
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| abstract render(props?: RenderableProps<P>, state?: Readonly<S>, context?: any): JSX.Element | null; | |||
| abstract render(props?: RenderableProps<P>, state?: Readonly<S>, context?: any): ComponentChild; | |||
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Thanks! I just ran into this myself in my own project
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