alt Hacker News> 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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Lately I've just been wondering if you couldn't have a python runtime for nix evaluations.
Ultimately we're taking inputs, making derivations and calling some nix specific library functions.
It feels like we should be able to do that with a Python library that would have the major advantage of being step debuggable.
Nix function call syntax is completely standard for ML-style functional languages and allows for effortless partial application. The main downside is that error messages can get cryptic, especially so when Nix is untyped.
Whitespace add list delimiter is not very common, but I have to admit I really like it.
I was hoping for some “this doesn’t work” kind of things, not “this doesn’t feel familiar”.
Not sure how Nix doesn’t win the readability contest: literally a config file with function calls, and as little superfluous syntax as possible. I’d say the real criticism is: Nix is hard to write, and nixpkgs idioms (nested, undocumentedabstractions scattered throughout the code) are hard to read.