Struct Coerce 

struct Coerce<D> {
    delegate: D,
    use_lub: bool,
    allow_two_phase: AllowTwoPhase,
    coerce_never: bool,
    cause: ObligationCause,
}

Fields

delegate: D

use_lub: bool

allow_two_phase: AllowTwoPhase

Determines whether or not allow_two_phase_borrow is set on any autoref adjustments we create while coercing. We don’t want to allow deref coercions to create two-phase borrows, at least initially, but we do need two-phase borrows for function argument reborrows. See rust#47489 and rust#48598 See docs on the “AllowTwoPhase” type for a more detailed discussion

coerce_never: bool

Whether we allow NeverToAny coercions. This is unsound if we’re coercing a place expression without it counting as a read in the MIR. This is a side-effect of HIR not really having a great distinction between places and values.

cause: ObligationCause

Implementations

impl<'db, D> Coerce<D>

where D: CoerceDelegate<'db>,

fn infcx(&self) -> &InferCtxt<'db>

fn param_env(&self) -> ParamEnv<'db>

fn interner(&self) -> DbInterner<'db>

fn db(&self) -> &'db dyn HirDatabase

pub(crate) fn commit_if_ok<T, E>( &mut self, f: impl FnOnce(&mut Self) -> Result<T, E>, ) -> Result<T, E>

fn unify_raw(&self, a: Ty<'db>, b: Ty<'db>) -> InferResult<'db, Ty<'db>>

fn unify( &mut self, a: Ty<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Unify two types (using sub or lub).

fn unify_and( &mut self, a: Ty<'db>, b: Ty<'db>, adjustments: impl IntoIterator<Item = Adjustment>, final_adjustment: Adjust, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Unify two types (using sub or lub) and produce a specific coercion.

fn coerce( &mut self, a: Ty<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

fn coerce_from_inference_variable( &mut self, a: Ty<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Coercing from an inference variable. In this case, we have no information about the source type, so we can’t really do a true coercion and we always fall back to subtyping (unify_and).

fn coerce_borrowed_pointer( &mut self, a: Ty<'db>, b: Ty<'db>, r_b: Region<'db>, mutbl_b: Mutability, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Reborrows &mut A to &mut B and &(mut) A to &B. To match A with B, autoderef will be performed, calling deref/deref_mut where necessary.

fn coerce_unsized( &mut self, source: Ty<'db>, target: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Performs [unsized coercion] by emulating a fulfillment loop on a CoerceUnsized goal until all CoerceUnsized and Unsize goals are successfully selected.

unsized coercion

fn coerce_from_safe_fn( &mut self, fn_ty_a: PolyFnSig<'db>, b: Ty<'db>, adjustment: Option<Adjust>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

fn coerce_from_fn_pointer( &mut self, fn_ty_a: PolyFnSig<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

fn coerce_from_fn_item( &mut self, a: Ty<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

fn coerce_closure_to_fn( &mut self, a: Ty<'db>, closure_def_id_a: InternedClosureId<'db>, args_a: GenericArgs<'db>, b: Ty<'db>, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>

Attempts to coerce from the type of a non-capturing closure into a function pointer.

fn coerce_raw_ptr( &mut self, a: Ty<'db>, b: Ty<'db>, mutbl_b: Mutability, ) -> InferResult<'db, (Vec<Adjustment>, Ty<'db>)>