Document expansion queries

This commit is contained in:
Aleksey Kladov 2021-05-04 22:40:10 +03:00
parent 3f6980e4e1
commit 1ea4dae596

View File

@ -87,24 +87,45 @@ impl TokenExpander {
pub trait AstDatabase: SourceDatabase {
fn ast_id_map(&self, file_id: HirFileId) -> Arc<AstIdMap>;
/// Main public API -- parsis a hir file, not caring whether it's a real
/// file or a macro expansion.
#[salsa::transparent]
fn parse_or_expand(&self, file_id: HirFileId) -> Option<SyntaxNode>;
/// Implementation for the macro case.
fn parse_macro_expansion(
&self,
macro_file: MacroFile,
) -> ExpandResult<Option<(Parse<SyntaxNode>, Arc<mbe::TokenMap>)>>;
/// Macro ids. That's probably the tricksiest bit in rust-analyzer, and the
/// reason why we use salsa at all.
///
/// We encode macro definitions into ids of macro calls, this what allows us
/// to be incremental.
#[salsa::interned]
fn intern_macro(&self, macro_call: MacroCallLoc) -> LazyMacroId;
/// Certain built-in macros are eager (`format!(concat!("file: ", file!(), "{}"")), 92`).
/// For them, we actually want to encode the whole token tree as an argument.
#[salsa::interned]
fn intern_eager_expansion(&self, eager: EagerCallLoc) -> EagerMacroId;
/// Lowers syntactic macro call to a token tree representation.
#[salsa::transparent]
fn macro_arg(&self, id: MacroCallId) -> Option<Arc<(tt::Subtree, mbe::TokenMap)>>;
/// Extracts syntax node, corresponding to a macro call. That's a firewall
/// query, only typing in the macro call itself changes the returned
/// subtree.
fn macro_arg_text(&self, id: MacroCallId) -> Option<GreenNode>;
/// Gets the expander for this macro. This compiles declarative macros, and
/// just fetches procedural ones.
fn macro_def(&self, id: MacroDefId) -> Option<Arc<TokenExpander>>;
/// Expand macro call to a token tree. This query is LRUed (we keep 128 or so results in memory)
fn macro_expand(&self, macro_call: MacroCallId) -> ExpandResult<Option<Arc<tt::Subtree>>>;
/// Special case of the previous query for procedural macros. We can't LRU
/// proc macros, since they are not deterministic in general, and
/// non-determinism breaks salsa in a very, very, very bad way. @edwin0cheng
/// heroically debugged this once!
fn expand_proc_macro(&self, call: MacroCallId) -> Result<tt::Subtree, mbe::ExpandError>;
/// Firewall query that returns the error from the `macro_expand` query.
fn macro_expand_error(&self, macro_call: MacroCallId) -> Option<ExpandError>;