Struct salsa_2022::function::FunctionIngredient

pub struct FunctionIngredient<C: Configuration> { /* private fields */ }

Function ingredients are the “workhorse” of salsa. They are used for tracked functions, for the “value” fields of tracked structs, and for the fields of input structs. The function ingredient is fairly complex and so its code is spread across multiple modules, typically one per method. The main entry points are:

• the fetch method, which is invoked when the function is called by the user’s code; it will return a memoized value if one exists, or execute the function otherwise.
• the specify method, which can only be used when the key is an entity created by the active query. It sets the value of the function imperatively, so that when later fetches occur, they’ll return this value.
• the store method, which can only be invoked with an &mut reference, and is to set input fields.

Implementations

impl<C> FunctionIngredient<C>where
    C: Configuration,

pub fn accumulated<'db, A>(&self, db: &DynDb<'db, C>, key: C::Key) -> Vec<A::Data>where
    DynDb<'db, C>: HasJar<A::Jar>,
    A: Accumulator,

Returns all the values accumulated into accumulator by this query and its transitive inputs.

impl<C> FunctionIngredient<C>where
    C: Configuration,

pub fn fetch(&self, db: &DynDb<'_, C>, key: C::Key) -> &C::Value

impl<C> FunctionIngredient<C>where
    C: Configuration,

pub fn specify_and_record<'db>(
    &self,
    db: &'db DynDb<'db, C>,
    key: C::Key,
    value: C::Value
)where
    C::Key: TrackedStructInDb<DynDb<'db, C>>,

Specify the value for key and record that we did so. Used for explicit calls to specify, but not needed for pre-declared tracked struct fields.

impl<C> FunctionIngredient<C>where
    C: Configuration,

pub fn store(
    &mut self,
    runtime: &mut Runtime,
    key: C::Key,
    value: C::Value,
    durability: Durability
)

impl<C> FunctionIngredient<C>where
    C: Configuration,

pub fn new(index: IngredientIndex, debug_name: &'static str) -> Self

pub fn set_capacity(&self, capacity: usize)

Trait Implementations

impl<DB, C> Ingredient<DB> for FunctionIngredient<C>where
    DB: ?Sized + DbWithJar<C::Jar>,
    C: Configuration,

fn maybe_changed_after(
    &self,
    db: &DB,
    input: DependencyIndex,
    revision: Revision
) -> bool

Has the value for input in this ingredient changed after revision?

fn cycle_recovery_strategy(&self) -> CycleRecoveryStrategy

If this ingredient is a participant in a cycle, what is its cycle recovery strategy? (Really only relevant to crate::function::FunctionIngredient, since only function ingredients push themselves onto the active query stack.)

fn origin(&self, key_index: Id) -> Option<QueryOrigin>

What were the inputs (if any) that were used to create the value at key_index.

fn mark_validated_output(
    &self,
    db: &DB,
    executor: DatabaseKeyIndex,
    output_key: Option<Id>
)

Invoked when the value output_key should be marked as valid in the current revision. This occurs because the value for executor, which generated it, was marked as valid in the current revision.

fn remove_stale_output(
    &self,
    _db: &DB,
    _executor: DatabaseKeyIndex,
    _stale_output_key: Option<Id>
)

Invoked when the value stale_output was output by executor in a previous revision, but was NOT output in the current revision.

fn reset_for_new_revision(&mut self)

Invoked when a new revision is about to start. This moment is important because it means that we have an &mut-reference to the database, and hence any pre-existing &-references must have expired. Many ingredients, given an &'db-reference to the database, use unsafe code to return &'db-references to internal values. The backing memory for those values can only be freed once an &mut-reference to the database is created.

fn salsa_struct_deleted(&self, db: &DB, id: Id)

Informs the ingredient self that the salsa struct with id id has been deleted. This gives self a chance to remove any memoized data dependent on id. To receive this callback, self must register itself as a dependent function using SalsaStructInDb::register_dependent_fn.

fn fmt_index(&self, index: Option<Id>, fmt: &mut Formatter<'_>) -> Result

impl<C> IngredientRequiresReset for FunctionIngredient<C>where
    C: Configuration,

const RESET_ON_NEW_REVISION: bool = true

If this is true, then reset_for_new_revision will be called every new revision.