build fails with stable and with nightly

[Bill Mill]

I tried installing with cargo install starlark, my system has rust stable set as the default. This fails with #![feature] may not be used on the stable release channel from the gazebo v0.6.0 package:

detailed error messages

error[E0554]: `#![feature]` may not be used on the stable release channel
  --> /Users/llimllib/.cargo/registry/src/github.com-1ecc6299db9ec823/gazebo-0.6.0/src/lib.rs:10:49
   |
10 | #![cfg_attr(feature = "str_pattern_extensions", feature(pattern))]
   |                                                 ^^^^^^^^^^^^^^^^

error[E0554]: `#![feature]` may not be used on the stable release channel
  --> /Users/llimllib/.cargo/registry/src/github.com-1ecc6299db9ec823/gazebo-0.6.0/src/lib.rs:11:49
   |
11 | #![cfg_attr(feature = "str_pattern_extensions", feature(associated_type_bounds))]
   |                                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error[E0554]: `#![feature]` may not be used on the stable release channel
  --> /Users/llimllib/.cargo/registry/src/github.com-1ecc6299db9ec823/gazebo-0.6.0/src/lib.rs:10:57
   |
10 | #![cfg_attr(feature = "str_pattern_extensions", feature(pattern))]

I then tried installing with nightly (with rustup toolchain install nightly and rustup run nightly cargo install starlark), which fails with feature has been removed for box_syntax:

detailed error messages

error[E0557]: feature has been removed
   --> /Users/llimllib/.cargo/registry/src/index.crates.io-6f17d22bba15001f/starlark-0.8.0/src/lib.rs:352:12
    |
352 | #![feature(box_syntax)]
    |            ^^^^^^^^^^ feature has been removed
    |
    = note: replaced with `#[rustc_box]`

error: `box_syntax` has been removed
   --> /Users/llimllib/.cargo/registry/src/index.crates.io-6f17d22bba15001f/starlark-0.8.0/src/assert/assert.rs:225:25
    |
225 |             setup_eval: box |_| (),
    |                         ^^^^^^^^^^
    |
help: use `Box::new()` instead
    |
225 |             setup_eval: Box::new(|_| ()),
    |                         ~~~~~~~~~~~~~~~~

and a few more errors:

error[E0407]: method `backtrace` is not a member of trait `Error`
   --> /Users/llimllib/.cargo/registry/src/index.crates.io-6f17d22bba15001f/starlark-0.8.0/src/errors/mod.rs:126:5
    |
126 | /     fn backtrace(&self) -> Option<&std::backtrace::Backtrace> {
127 | |         Some(self.message.backtrace())
128 | |     }
    | |_____^ not a member of trait `Error`

error[E0512]: cannot transmute between types of different sizes, or dependently-sized types
  --> /Users/llimllib/.cargo/registry/src/index.crates.io-6f17d22bba15001f/starlark-0.8.0/src/syntax/ast.rs:84:1
   |
84 | assert_eq_size!(AstStmt, [usize; 12]);
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: source type: `Spanned<StmtP<AstNoPayload>>` (704 bits)
   = note: target type: `[usize; 12]` (768 bits)
   = note: this error originates in the macro `assert_eq_size` (in Nightly builds, run with -Z macro-backtrace for more info)

error[E0512]: cannot transmute between types of different sizes, or dependently-sized types
  --> /Users/llimllib/.cargo/registry/src/index.crates.io-6f17d22bba15001f/starlark-0.8.0/src/syntax/ast.rs:85:1
   |
85 | assert_eq_size!(AstExpr, [usize; 9]);
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: source type: `Spanned<ExprP<AstNoPayload>>` (448 bits)
   = note: target type: `[usize; 9]` (576 bits)
   = note: this error originates in the macro `assert_eq_size` (in Nightly builds, run with -Z macro-backtrace for more info)

How can I install starlark-rust? I'm at the limit of my rust knowledge here.

[Stepan Koltsov]

We need to release new version which is compatible with stable.

For now the best option is to use some older nightly before box_syntax was removed. We are using nightly-2023-01-24 currently.

[Bill Mill]

I randomly tried using 2023-01-01, but it failed - possibly I was doing it wrong.

Anyway, installing from HEAD with: rustup run nightly cargo install --git https://github.com/facebookexperimental/starlark-rust starlark seems to have worked.

Thanks for the quick response!

[Stepan Koltsov]

Note starlark has very simple command line interface, but primary purpose of starlark is to be embedded in another program.

[Bill Mill]

I want to use it as my lsp, I bought a tidbyt which uses starlark as its programming language, and nvim-lsp supports this program as an lsp

[Neil Mitchell]

Usually most "Starlark" things have a bunch of extra functions, and those won't be available in the LSP unless you teach it. The way you teach it is by writing a Rust program that builds on the starlark-rust library. If you do this seriously, you'll probably want to switch to that, but for getting started the generic version probably works fine.

[Bill Mill]

I am doing this as unseriously as possible 🤣