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Comment by Blikkentrekker | Hacker News Reader

I feel languages should just have some kind of sugar or operator for this, in fact in Ocaml the |> operator exists where

   <exp> |> <exp2>
   <exp2>(<exp>)

Are just one and the same

For a variadic language you'd need something more involved though. But some kind of syntax can probably be invented in some language.

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It's common to write the thrush combinator as a lisp macro. Clojure ships ->, ->>, as->, some->, some->>, cond->, and cond->> out of the box. You can find similar macros for CL[0], Racket[1], and a scheme SRFI[2]. Writing them is a fun exercise in your lisp of choice if you don't have a library available.

[0] https://github.com/dtenny/clj-arrows

[1] https://docs.racket-lang.org/threading/index.html

[2] https://srfi.schemers.org/srfi-197/srfi-197.html

Elixir has it. To make it worthwhile, the entire standard library has to be designed to have the ‘object’ of the function as first argument.

   [1,2,3]
   |> Enum.map(&square/1)
   |> Enum.filter(&odd?/1)

Using a threading operator where there is no such consistency is painful. This is why I dislike CL’s or Python’s map function, taking the list to operate on as second argument, instead of first. A threading operator wouldn’t be as effective there.

The issue is that these functions in Lisps are variadic and can accept more arguments than one. `map`, and `zipwidth` in lisps are actually the same function.

Taking the object as the last argument works just as well. Just needs to be consistent whichever way is chosen.

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