Enum UnifyError 

pub enum UnifyError {
    SymbolClash {
        left: String,
        right: String,
    },
    ArityMismatch {
        expected: usize,
        found: usize,
    },
    OccursCheck {
        var: u32,
    },
}

Error type for unification failures.

Variants

SymbolClash

The two terms have different top-level function symbols.

Fields

left: String

right: String

ArityMismatch

The two terms have different numbers of arguments.

Fields

expected: usize

found: usize

OccursCheck

A variable occurs in the term it would be unified with (infinite term).

Fields

var: u32

Trait Implementations

impl Clone for UnifyError

fn clone(&self) -> UnifyError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for UnifyError

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

Formats the value using the given formatter.

impl Display for UnifyError

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

Formats the value using the given formatter.

impl Error for UnifyError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

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

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl PartialEq for UnifyError

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for UnifyError

impl StructuralPartialEq for UnifyError