pub struct PrivExternTypeDeclarationDataQuery;Implementations§
source§impl PrivExternTypeDeclarationDataQuery
 
impl PrivExternTypeDeclarationDataQuery
sourcepub fn in_db(self, db: &dyn SemanticGroup) -> QueryTable<'_, Self>
 
pub fn in_db(self, db: &dyn SemanticGroup) -> QueryTable<'_, Self>
Get access to extra methods pertaining to this query. For
example, you can use this to run the GC (sweep) across a
single input. You can also use it to invoke this query, though
it’s more common to use the trait method on the database
itself.
source§impl PrivExternTypeDeclarationDataQuery
 
impl PrivExternTypeDeclarationDataQuery
sourcepub fn in_db_mut(self, db: &mut dyn SemanticGroup) -> QueryTableMut<'_, Self>
 
pub fn in_db_mut(self, db: &mut dyn SemanticGroup) -> QueryTableMut<'_, Self>
Like in_db, but gives access to methods for setting the
value of an input. Not applicable to derived queries.
Threads, cancellation, and blocking
Mutating the value of a query cannot be done while there are
still other queries executing. If you are using your database
within a single thread, this is not a problem: you only have
&self access to the database, but this method requires &mut self.
However, if you have used snapshot to create other threads,
then attempts to set will block the current thread until
those snapshots are dropped (usually when those threads
complete). This also implies that if you create a snapshot but
do not send it to another thread, then invoking set will
deadlock.
Before blocking, the thread that is attempting to set will
also set a cancellation flag. In the threads operating on
snapshots, you can use the is_current_revision_canceled
method to check for this flag and bring those operations to a
close, thus allowing the set to succeed. Ignoring this flag
may lead to “starvation”, meaning that the thread attempting
to set has to wait a long, long time. =)
Trait Implementations§
source§impl Default for PrivExternTypeDeclarationDataQuery
 
impl Default for PrivExternTypeDeclarationDataQuery
source§fn default() -> PrivExternTypeDeclarationDataQuery
 
fn default() -> PrivExternTypeDeclarationDataQuery
source§impl Query for PrivExternTypeDeclarationDataQuery
 
impl Query for PrivExternTypeDeclarationDataQuery
§type Key = ExternTypeId
 
type Key = ExternTypeId
§type Value = Result<ExternTypeDeclarationData, DiagnosticAdded>
 
type Value = Result<ExternTypeDeclarationData, DiagnosticAdded>
§type Storage = DerivedStorage<PrivExternTypeDeclarationDataQuery, AlwaysMemoizeValue>
 
type Storage = DerivedStorage<PrivExternTypeDeclarationDataQuery, AlwaysMemoizeValue>
source§const QUERY_INDEX: u16 = 117u16
 
const QUERY_INDEX: u16 = 117u16
source§const QUERY_NAME: &'static str = _
 
const QUERY_NAME: &'static str = _
foo)