Enum Silence 

pub enum Silence {
    NotAConstant,
    Undefined,
    Unanswered,
    Unexamined,
}

Why the engine’s answer names no value.

Variants

NotAConstant

A mechanism rather than a constant: the value chains off a sibling, or off whatever the object held, and no literal describes it.

Undefined

The object is allocated without being zeroed and nothing assigns the member, so an absent field leaves whatever the memory held.

Unanswered

Somebody looked and the page does not say.

Unexamined

Nobody has looked.

Trait Implementations

impl Clone for Silence

fn clone(&self) -> Silence

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Silence

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

Formats the value using the given formatter.

impl PartialEq for Silence

fn eq(&self, other: &Silence) -> 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 Copy for Silence

impl Eq for Silence

impl StructuralPartialEq for Silence