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sshinelast Friday at 11:11 PM2 repliesview on HN

> The remaining syntax has a lot of "but why?" where it just seems to do its own thing relative to other languages

Like what?

My list of Nix language nits is relatively small, would like to understand.

One thing that seems under-developed is smart merging. There is // at language level, but then if you want datatype-specific merging, you use functions. That itself is just the power of functional programming. But as it is with untyped languages, you end up doing the same thing slightly different in several places, and a fractal of accidental complexity starts to appear.


Replies

positron26yesterday at 1:53 AM

> Like what?

I've heard people say "JSON with functions", but I think this is much too generous.

- Functions can be called without delimiters

- AttrSets have lots of delimiting, very explicit syntax

- Lists have absolutely no delimiters again

foo 1 2 is a function call, right?

So if I need it in a list, I can just write: [ foo 1 2 ] right?

Note, we pathologically put spaces around lists in Nix because we are subconsciously sure that something is about to bite us.

[ foo 1 2 ] is a list of three elements, not a function call.

I forget which terrible thing I was doing, but I had a variation of this syntax trap in my code after naively moving the expression into a list. The error message was, as usual, from the Turtles in Time dimension.

The mixture of super explicit and implicit delimiting as well as borrowed ideas like \\ and invented ideas like with and import just make Nix feel like it's all over the place, inconsistent, and doing its own thing when we already had a lot of functional languages to work with.

The evaluation model is completely appropriate for the problem yet pretty unique in programming generally. It has a lot of new ideas that throw even seasoned people well off track. Each new idea is not much, but they compound into not having any idea what we're looking at and watching 50k nixpkgs evaluate just fine while not being able to read any of that code at all.

I'd prefer something like Haskell, Lisp, or Clojure, but please just one. Using Scheme in Guile is a great choice. It's so much easier to read. Hopefully the macros can be developed to bring the best of lazy evaluation into Scheme and fix the runtime issues.

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chriswarboyesterday at 1:34 AM

> One thing that seems under-developed is smart merging.

Maybe https://codeberg.org/amjoseph/infuse.nix would be useful? (I find it intriguing, but haven't yet faced a use-case that seemed worth learning it)