Enum KeyConflictError 

pub enum KeyConflictError<K1, K2, V = ()> {
    Key1Exists(K1, K2, V),
    Key2Exists(K1, K2, V),
    BothKeysExist(K1, K2, V),
}

Error returned by DoubleMap::insert and DoubleMap::entry when one or both of the supplied keys clash with an existing entry in the map.

The rejected keys are returned in the variant payload so the caller can reuse them without cloning. insert additionally returns the rejected value, so its error type is KeyConflictError<K1, K2, V>; entry has no value to hand back and uses the default V = ().

Variants

Key1Exists(K1, K2, V)

key1 is already present in the map (paired with a different key2), while the supplied key2 is not in the map.

Key2Exists(K1, K2, V)

key2 is already present in the map (paired with a different key1), while the supplied key1 is not in the map.

BothKeysExist(K1, K2, V)

Both key1 and key2 are already present in the map, but in different entries.

Trait Implementations

impl<K1: Debug, K2: Debug, V: Debug> Debug for KeyConflictError<K1, K2, V>

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

Formats the value using the given formatter.

impl<K1, K2, V> Display for KeyConflictError<K1, K2, V>

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

Formats the value using the given formatter.

impl<K1, K2, V> Error for KeyConflictError<K1, K2, V>

where Self: Debug + Display,

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.