Changes void to unknown for callback definitions. #462
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A callback like `() => void` means that the caller must provide a function that is explicitly void returning. This means one cannot pass a function as a callback that may have a return value that is ignored. By changing the required return type to `unknown`, it allows the caller to provide either a void returning function, or a function that returns a value. This is especially valuable when you have callback functions like `() => condition && doThing()`. Such a function returns a boolean value, which makes it incompatible with `() => void` callback requirements. You can work around this by wrapping the body with curly braces (to throw away the result of the expression), but it is better to be permissive in what is accepted instead.
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I ran Regarding react, I don't use/haven't used react so I'm not sure how this would be ported over to that. |
Looks great, thanks! Just helps us keep track of changes and what needs to be released.
I might be able to take a look later, but generally it would just be applying the same thing I'd think (+ to |
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I do see this, which certainly seems related. Does that need to be changed as well? |
| @@ -356,7 +356,7 @@ export function useComputed<T>(compute: () => T) { | |||
| return useMemo(() => computed<T>(() => $compute.current()), []); | |||
| } | |||
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| export function useSignalEffect(cb: () => void | (() => void)) { | |||
| export function useSignalEffect(cb: () => unknown | (() => unknown)) { | |||
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What's the type of the callback passed to effect? Should this type match that since this callback is invoked inside of an effect and its return value is passed to effect? IIRC, effect accepts a clean up function
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Hmm, good point. We could make the change from
useEffect(() => {
return effect(() => callback.current());
}, []);to
useEffect(() => {
return effect(() => { callback.current() });
}, []);This would ensure that effect is getting a void returning function. Alternatively, we could change the definition of effect, but I think that is in a different repository?
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I went ahead and made the above change to this PR, can revert if another solution is desired.
A callback like
() => voidmeans that the caller must provide a function that is explicitly void returning. This means one cannot pass a function as a callback that may have a return value that is ignored. By changing the required return type tounknown, it allows the caller to provide either a void returning function, or a function that returns a value.This is especially valuable when you have callback functions like
() => condition && doThing(). Such a function returns a boolean value, which makes it incompatible with() => voidcallback requirements. You can work around this by wrapping the body with curly braces (to throw away the result of the expression), but it is better to be permissive in what is accepted instead.