Enum Exists 

pub enum Exists {
    Always,
    IfMissing,
    IfPresent,
}

Whether a SET should go ahead given what is already there.

Variants

Always

Store whatever is there. Plain SET.

IfMissing

Only if the key is absent. SET NX, and SETNX.

IfPresent

Only if the key is present. SET XX.

Trait Implementations

impl Clone for Exists

fn clone(&self) -> Exists

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Exists

impl Debug for Exists

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

Formats the value using the given formatter.

impl Default for Exists

fn default() -> Exists

Returns the “default value” for a type.

impl Eq for Exists

impl PartialEq for Exists

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Exists