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0 pointsmomentoftop4d ago0 comments

> It's extremely rare that you need to (printf "%d %d" foo)

I write stuff like `map (printf "%d %d" m) ns` all the time. I daresay I even do the map as a partial application, so double currying.

0 comments

gf0004d ago

But arguably your intent would be much more clear with something like `map (printf "%d %d" m _) ns` or a lambda.

I don't think parent is saying that partial application is bad, far from it. But to a reader it is valuable information whether it's partial or full application.

octachron3d ago

Not really when reading `iter (printf %"d %d" m) ns`, I am likely to read it in three steps

  - `iter`: this is a side-effect on a collection
  - `(printf`: ok, this is just printing, I don't care about what is printed, let's skip to the `)`
  - ns: ok, this is the collection being printed

Notice that having a lambda or a partial application `_` will only add noise here.

> But to a reader it is valuable information whether it's partial or full application.

This can be a valuable information in some context, but in a functional language, functions are values. Thus a "partial application" (in term of closure construction) might be better read as a full application because the main type of concern in the current context is a functional type.

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