In theory because none are allowed. This is to improve consistency in
handle_decl_name_scope's modifier handling, removing the namespace
special-case.
I noticed there's a crash bug on `impl <declaration>` which I'll address
separately.
This builds on #3461.
This is supporting a direction that all parse nodes should correspond to
a single token, allowing for reduced tokenized buffer access during
checking (it's still necessary for diagnostics, and some literals).
One of the justifications for a unified parse node was implementation
LOC: note this is slightly smaller, using macros to reduce some
duplication. While this does add more switching in HandleDeclScopeLoop,
that's offset by less explicit switching in the check handlers. Also, I
think the duplication in HandleDeclScopeLoop can be reduced by shifting
the flow there, which I'll do in a separate PR.
This should cover:
```
library "lib" api;
import Foo library default;
import library default;
import library "lib";
```
This splits out `PackageName` and `LibraryName` to their own parse nodes
so that checking can ignore them and still get a balanced parse tree
(otherwise, we essentially need to implement handling of the parse nodes
only to remove the identifiers/string literals -- the optional names
mean we can't blindly do that as before). For reference, these nodes
don't need to be handled because CheckParseTree will need to directly
funnel import information along with checked IRs.
For now, we require the same introducer to be used each time a class is
declared, but see #3384.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Jon Ross-Perkins
josh11b
Richard Smith