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0 pointsabritinthebay9y ago0 comments

Sure, it would be an odd pattern but perhaps a required one for a certain interface.

eg: it's going to be used as a event callback but you want the function signature to be foo(bar, event). Then you get the benefits of partial application without the problems of currying a new function each time its called.

source: have used this a lot for event handlers, especially when dealing with on 3rd party code.

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aidos9y ago· 2 in thread

I don't quite understand. The interface is the same. I guess if the function you're binding is an external 3rd party one then you avoid proxying through a local function first. But there's no difference from the point of view of the child.

I guess my point was that it doesn't scale to multiple children (which is effectively what the question was about). And whether you want to partially apply a bound function in the constructor or just bind and then have the function pick up the extra arg itself - it's the same thing. You end up with a single function that works with a single constant.

Though, in your case if props change, the partially applied function is now incorrect. Which is why I think I'm misunderstanding you.

abritinthebayOP9y ago

Right, I just used `props.bar` in that example, you're right - it would be a bad idea to do so unless it was some kind of initializing prop (common with state-based stuff).

> The interface is the same.

Huh? foo(event) is different from foo(bar, event) and if your function is only ever going to be called with the former (ie - any dom event handler) and you want the latter... it's absolutely useful.

aidos9y ago

I rather meant the interface between the partially applied foo and the version of foo that plucks bar from props when it's called.

Anyway, I see what you mean and it's a perfectly reasonable thing to do. Doesn't solve the original issue that was being discussed though :-)

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