# Enum chalk_ir::GoalData

``````pub enum GoalData<I: Interner> {
Quantified(QuantifierKind, Binders<Goal<I>>),
Implies(ProgramClauses<I>, Goal<I>),
All(Goals<I>),
Not(Goal<I>),
EqGoal(EqGoal<I>),
SubtypeGoal(SubtypeGoal<I>),
DomainGoal(DomainGoal<I>),
CannotProve,
}``````
Expand description

A general goal; this is the full range of questions you can pose to Chalk.

## Variants

### `Quantified(QuantifierKind, Binders<Goal<I>>)`

Introduces a binding at depth 0, shifting other bindings up (deBruijn index).

### `Implies(ProgramClauses<I>, Goal<I>)`

A goal that holds given some clauses (like an if-statement).

### `All(Goals<I>)`

List of goals that all should hold.

### `Not(Goal<I>)`

Negation: the inner goal should not hold.

### `EqGoal(EqGoal<I>)`

Make two things equal; the rules for doing so are well known to the logic

### `SubtypeGoal(SubtypeGoal<I>)`

Make one thing a subtype of another; the rules for doing so are well known to the logic

### `DomainGoal(DomainGoal<I>)`

A “domain goal” indicates some base sort of goal that can be proven via program clauses

### `CannotProve`

Indicates something that cannot be proven to be true or false definitively. This can occur with overflow but also with unifications of skolemized variables like `forall<X,Y> { X = Y }`. Of course, that statement is false, as there exist types X, Y where `X = Y` is not true. But we treat it as “cannot prove” so that `forall<X,Y> { not { X = Y } }` also winds up as cannot prove.

## Implementations

Create an interned goal.

## Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from `source`. Read more
Formats the value using the given formatter. Read more
The interner associated with the type.
Feeds this value into the given `Hasher`. Read more
Feeds a slice of this type into the given `Hasher`. Read more
This method tests for `self` and `other` values to be equal, and is used by `==`. Read more
This method tests for `!=`. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
Apply the given folder `folder` to `self`; `binders` is the number of binders that are in scope when beginning the folder. Typically `binders` starts as 0, but is adjusted when we encounter `Binders<T>` in the IR or other similar constructs. Read more
A convenient alternative to `try_fold_with` for use with infallible folders. Do not override this method, to ensure coherence with `try_fold_with`. Read more
Apply the given visitor `visitor` to `self`; `binders` is the number of binders that are in scope when beginning the visitor. Typically `binders` starts as 0, but is adjusted when we encounter `Binders<T>` in the IR or other similar constructs. Read more
Uses the zipper to walk through two values, ensuring that they match.

## Blanket Implementations

Gets the `TypeId` of `self`. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more
Cast a value to type `U` using `CastTo`.
Checks whether `self` and `other` could possibly match.

Returns the argument unchanged.

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

Shifts this term in one level of binders.
Shifts a term valid at `outer_binder` so that it is valid at the innermost binder. See `DebruijnIndex::shifted_in_from` for a detailed explanation. Read more
Shifts a term valid at the innermost binder so that it is valid at `outer_binder`. See `DebruijnIndex::shifted_out_to` for a detailed explanation. Read more
Shifts this term out one level of binders.
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
Check whether there are free (non-bound) variables.