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Comment by hinkley | Hacker News Reader

The pipe operator relies on the first argument being the subject of the operation. A lot of languages have the arguments in a different order, and OO languages sometimes use function chaining to get a similar result.

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IIRC the usual workaround in Elixir involves be small lambda that rearranges things:

    "World"
    |> then(&concat("Hello ", &1))

I imagine a shorter syntax could someday be possible, where some special placeholder expression could be used, ex:

    "World"
    |> concat("Hello ", &1)

However that creates a new problem: If the implicit-first-argument form is still permitted (foo() instead of foo(&1)) then it becomes confusing which function-arity is being called. A human could easily fail to notice the absence or presence of the special placeholder on some lines, and invoke the wrong thing.

Yeah I really hate that syntax and I can’t even explain why so I kind of blot it out, but you’re right.

My dislike does improve my test coverage though, since I tend to pop out a real method instead.

Yeah, R (tidyverse) has `.` as such a placeholder. It is useful but indeed I find the syntax off, though I find the syntax off even without it, anyway. I would rather define pipes as compositions of functions, which are pretty unambiguous in terms of what arguments they get, and then apply these to whatever i want.

Last time I checked (2020) there were already a few rejected proposals to shorten the syntax for this. It seemed like they were pretty exasperated by them at the time.

Swiss arrows ftw!

https://github.com/rplevy/swiss-arrows https://github.com/hipeta/arrow-macros

You could make use of `flip` from Haskell.

    flip :: (x -> y -> z) -> (y -> x -> x)
    flip f = \y -> \x -> f x y

    x |> (flip f)(y)    -- f(x, y)

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