Issue#8 limit happy to less than 2.1 #46
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Previously the instance was incorrect because it'd cause an infinite loop. This version rearranges the fields of the records to ensure that the hash field is first, which makes it possible to derive Eq and Ord. We also do a bunch of refactoring to use record notation instead of constructor pattern matching, to make it easier to do similar refactoring in the future.
This reverts commit 9ff9176. Per the discussion in #6, having the `Eq` and `Ord` instances ignore the `raw` field of `Ident` causes more trouble than it's worth, as it causes the parser to incorrectly deem raw identifiers like `r#return` to be keywords. While we could fix this issue by changing the parser, this would take quite a bit of code changes to accomplish. As such, we revert the change here, and we make a note in the Haddocks for the `Eq` and `Ord` instances to beware of the fact that `raw` is taken into account. After this change, the `rustc-tests` test suite passes once more. As such, this change fixes #6.
Make tests pass, migrate to GitHub Actions
The previous lexer implementation in `Language.Rust.Parser.Lexer` was broken for Unicode characters with sufficiently large codepoints, as the previous implementation incorrectly attempted to port UTF-16–encoded codepoints over to `alex`, which is UTF-8–encoded. Rather than try to fix the previous implementation (which was based on old `rustc` code that is no longer used), this ports the lexer to a new implementation that is based on the Rust `unicode-xid` crate (which is how modern versions of `rustc` lex Unicode characters). Specifically: * This adapts `unicode-xid`'s lexer generation script to generate an `alex`-based lexer instead of a Rust-based one. * The new lexer is generated to support codepoints from Unicode 15.1.0. (It is unclear which exact Unicode version the previous lexer targeted, but given that it was last updated in 2016, it was likely quite an old version.) * I have verified that the new lexer can lex exotic Unicode characters such as `𝑂` and `𐌝` by adding them as regression tests. Fixes #3.
Lexer: Properly support Unicode 15.1.0
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Fixes #8. Adds an upper bound to
happyto not use 2.1