Enum evaltrees::typeck::TypeError

pub enum TypeError {
    CantUnify(Ty, Ty),
    Freevars(BTreeSet<Symbol>),
    MutualRecursion(Symbol),
    Occurs(SubstVar, Ty),
}

An error during typechecking.

Variants

CantUnify(Ty, Ty)

A constraint between two types couldn't be unified.

Freevars(BTreeSet<Symbol>)

A variable was undefined. This technically isn't a type error, but the error is only found during type-checking.

MutualRecursion(Symbol)

A mutually-recursive declaration was found. We don't currently support these.

Occurs(SubstVar, Ty)

The occurs check was failed (we've got an infinite type on our hands!).

Trait Implementations

impl Clone for TypeError

fn clone(&self) -> TypeError

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TypeError

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Fail for TypeError

fn cause(&self) -> Option<&Fail>

Returns a reference to the underlying cause of this failure, if it is an error that wraps other errors.

fn backtrace(&self) -> Option<&Backtrace>

Returns a reference to the Backtrace carried by this failure, if it carries one.

fn context<D>(self, context: D) -> Context<D> where     D: Display + Send + Sync + 'static,

Provides context for this failure.

fn compat(self) -> Compat<Self>

Wraps this failure in a compatibility wrapper that implements std::error::Error.

fn causes(&self) -> Causes

Returns a iterator over the causes of this Fail with itself as the first item and the root_cause as the final item.

fn root_cause(&self) -> &(Fail + 'static)

Returns the "root cause" of this Fail - the last value in the cause chain which does not return an underlying cause.

impl Display for TypeError

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.

impl PartialEq for TypeError

fn eq(&self, other: &TypeError) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &TypeError) -> bool

This method tests for !=.