Enum polytype::UnificationError

pub enum UnificationError {
    Occurs(Variable),
    Failure(Type, Type),
}

Represents errors in unification.

Variants

Occurs(Variable)

Occurs happens when occurs checks fail (i.e. a type variable is unified recursively). The id of the bad type variable is supplied.

Failure(Type, Type)

Failure happens when symbols or type variants don't unify because of structural differences.

Trait Implementations

impl Debug for UnificationError

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Clone for UnificationError

fn clone(&self) -> UnificationError

Returns a copy of the value.

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

Performs copy-assignment from source.

impl PartialEq for UnificationError

fn eq(&self, __arg_0: &UnificationError) -> bool

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

fn ne(&self, __arg_0: &UnificationError) -> bool

This method tests for !=.

impl Display for UnificationError

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

Formats the value using the given formatter.

impl Error for UnificationError

fn description(&self) -> &str

A short description of the error.

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

The lower-level cause of this error, if any.