mirror of
https://github.com/carbon-language/carbon-lang.git
synced 2026-09-25 14:10:11 +01:00
Jon Ross-Perkins
550559e30e
Note #3486 rewrites the macro behavior, and is already approved: so this PR is only for the changed enforcement during error. Also, #3493 already changed several things to allow any token while this PR was awaiting review, but this still changes enforcement for `For` and `If`. This was brought up on [#toolchain](https://discord.com/channels/655572317891461132/655578254970716160/1182066616456970251), and I think this any-on-error approach gets at least some support. We could try setting it to the introducer, but it's quite possible we want it to be something like the token which led to the parse error, rather than a static token. That leads to a conclusion that, most typically, we'll expect arbitrary tokens when error conditions may lead to tokens which aren't the expected token. A couple related, recent `CARBON_IF_ERROR` crash fixes can be found in #3404 and #3424. Something like #3404 would've been needed regardless because `namespace` didn't have `CARBON_IF_ERROR` before, although I might've missed the underlying issue with declarations because only `namespace` had a relevant test (that is, if #3404 had added `CARBON_ANY_TOKEN_ON_ERROR`, I wouldn't have had a crash in #3462). #3424 would've been avoided with this change because there was a `CARBON_IF_ERROR`, and it was just too restrictive.