[Python-ideas] Dollar operator suggestion

[Paul Moore]

On 26 October 2017 at 13:53, Daniel Moisset <dmoisset at machinalis.com> wrote:
> This is to clarify that this si NOT about function composition, just an alternate
> application syntax

The idea is already dead, based on the quote from Guido, but this
makes it even more clear that it's inappropriate for Python. As you
said (in part that I trimmed) Haskell uses single-argument functions
plus currying to implement function calls. This is extremely common
for functional languages, as it matches the theoretical basis much
better. As you point out, the shell pipeline model is actually quite
similar (a single input, chain of processing model).

Procedural languages, and Python in particular, simply don't work like
that. Functions have arbitrary numbers of arguments, currying is not
built in, composition is not a fundamental operation in the same way.
Although it's possible to explain how a `$` style syntax would work,
it doesn't fit naturally into the language - certainly not naturally
enough to warrant being part of the language syntax.

Paul