R.merge and type intersection about npm-ramda HOT 5 CLOSED

More info on this.

It looks like the problem is a conflict in these two definitions:

merge<T2>(a: R.placeholder, b: T2): <T1>(a: T1) => T1&T2;
merge<T1, T2>(a: T1, b: T2): T1 & T2;

Removing the first one fixes the issue.

I recommend reviewing (and possibly removing) the R.placeholder variation in favor simplifying the most common use-case (at least in my experience) of using R.merge with one or two objects.

Incidentally, any R.placeholder scenario can be replaced with a R.flip(R.merge).

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I just came up with the same finding after 8 days ;)
This works indeed.

The placeholder thing is something I'm not happy with at all. It doesn't fit typescript well, although I do see its use-case. It is probably better to make a clear choice and just not support them at all.

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The placeholder thing is something I'm not happy with at all. (...) It is probably better to make a clear choice and just not support them at all.

Agreed, we decided not to use R.__ at all in our codebase (since it felt more obscure than the R.flip alternative).

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I'll shoot a PR with the placeholders removed. If there are no serious objections, we remove them definitely.

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Cool @donnut , thanks!

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