[zoidb]

I have written a bit of both, recently re-wrote a command runner for a side-project https://gitlab.com/jarv/cmdchallenge in Nim and found it very pleasant and much less verbose, which was a nice change from GoLang while keeping type safety. A good example is parsing JSON https://nim-by-example.github.io/json/ as you can do a lot with fewer lines of code. I think the main disadvantage of Nim is that there is less out there in the ecosystem, libraries, and it's more likely you will run into quirks and bugs in the standard library.

[andybak]

I really like the look of Nim but every time I dig into it I find a really strange syntax decision. For example:

> The json module provides the %* operator which is used to create JSON objects

I'm curious what the benefits are here of an operator over some more readable syntax. I have a dislike of languages where ascii noise seems to be favoured over readable english tokens.

[k__]

This is interesting, especially for a language like Nim that favours familiarity with Python.

Even Rust dropped most of its strange operators/sigils early on in the experimentation phase, because they confused people and Rust doesn't step back from confusing people lightly, haha.

[elcritch]

Probably because Rust already has too many ascii symbols! ;) I still get brain mush remapping Rust's & from C's &.

But yah Nim's % is a bit strange at first, but becomes fairly handy in practice when dealing with lots a small bits of JSON. There's the % "to json" operator that mimics the $ "to string" operator for a single value. Then %* was added to handle multiple json items (I read it like apply % to all items). So it has a decent symmetry. Other than % and $ ascii operators are pretty rare in Nim code. Even bitops use or, and, shl, shr, etc over ascii operators.

[haxscramper]

This way you can write json literals in the code, and it will look just like regular json. For serialization and deserialization stdlib uses `to/load/store` proc names.

  import std/json

  echo %*{
    "key1": "value",
    "key2": 12,
  }

[clusterfish]

Could have just used a "JSON" keyword instead. Symbolic names are needlessly obscure and unfriendly. Hard to infer meaning, hard to pronounce, hard to search online, etc.

[dunefox]

As if "json" is any more searchable. Operators have a meaning that you learn quickly when learning the language. You wouldn't do math with "multiply" instead of "*", so why would you want that in a programming language?

[mkl]

Multiply already has a symbol, and JSON already has a name. Making up a symbol %* to mean JSON is like making up a name Flurb to mean *. Sticking with what already exists seems much simpler.

[dandellion]

Because with a keyword the meaning is much more explicit, and I consider that to be more valuable. And I think "*" is a bad example because pretty much everyone who programs already knows it's multiplication.

[dunefox]

It might not be the best example, but the point stands. Succinct notation is important. "JSON" instead of "%*" might not be the greatest of examples but still.

[mixedCase]

Because there's no point in saving three characters (although I'd rather have it be "literal_json" or "inline_json") just to have people memorize what yet another symbol means in a highly specialized context when you could just read the word and be perfectly certain what the code means without looking it up the first time.

Even after the first time symbols have a non-trivial cognitive cost for a lot of people, if not most, all while providing near zero benefit unless your app is pretty much nothing but a bunch of inline json expansions.

[clusterfish]

Of course it is. It's descriptive and searchable.

Because * / - + is the common ground that essentially everyone is familiar with. And that's about as much math notation as makes sense in general purpose programming languages.

There is only one math but many programming languages. Multiplication is universal and fundamental. Creating JSON objects in nim is the opposite of that.

[dunefox]

> Of course it is. It's descriptive and searchable.

If I entered "nim json" into google I'd get thousands of results for the language and json in general, and no way to narrow it down to meaning the operator "JON". That's not really what searchable means.

[timotheecour]

Checkout the newer std/jsonutils: https://nim-lang.github.io/Nim/jsonutils.html

let a = (1.5'f32, (b: "b2", a: "a2"), 'x', @[Foo(t: true, z1: -3), nil])

let j = a.toJson

assert j.jsonTo(typeof(a)).toJson == j

[zoidb]

Yeah, I tend to agree with you here especially after a take a break from writing Nim I need to re-learn a lot because it is impossible to hold it in my head for very long.

[vegai_]

That's really good point. Also, I don't think it's the only weird operator they introduce in the stdlib without any good reason.

[xigoi]

The json module is old and probably wouldn't be designed this way today.

[Thaxll]

That %* is really strange. Also in the example there is no notion of errors? Nim is exception based?

[timotheecour]

yes, invalid JSON would raise an exception.