Stream: ideas

Topic: piping the function argument

Oskar Hahn (Dec 03 2023 at 11:05):

I like the possibility, to pipe values between functions. In a lot of cases, I have a function, that takes one argument and pipes it into a stream of functions

myFunc : \arg ->
  arg
  |> doSomething
  |> doSomethingElse
  |> doMore

What is a bit strange is, that I have to write the argument two times. One time as argument, and one time at the beginning of the piping.

In elm, I had the possibility, to pipe the argument to the first function without writing it :

myFunc =
  doSomething
  >> doSomethingElse
  >> doMore

I don't like the elm style, since it is hard to see, that the function takes an argument. I have to write the argument two times or zero times.

It would be nice, if I could write the argument only once.

Would the following be possible?

myFunc : \arg ->
  |> doSomething
  |> doSomethingElse

If a function has only one argument and the function starts with |>, then the argument is piped into the first function.

Would it be possible to implement this kind of syntax sugar?

Declan Joseph Maguire (Dec 03 2023 at 13:10):

I'd literally been thinking about this earlier today. Didn't post it because I felt I'd already done enough bikeshedding elsewhere about minor matters of syntax regarding pipelines and lambdas

LoipesMas (Dec 03 2023 at 14:02):

I think this falls in the same category as pointfree function composition (although the order of operations is inversed), so I guess the same downsides apply? I.e., conciseness vs readability/intuitiveness

Last updated: Jun 16 2026 at 16:19 UTC