pub trait Optional: Copy {
type Inner: Copy;
// Required methods
fn none() -> Self;
fn some(v: Self::Inner) -> Self;
fn is_none(&self) -> bool;
fn inner(&self) -> Option<Self::Inner>;
// Provided method
fn is_some(&self) -> bool { ... }
}Expand description
To represent empty trie entry.
Provided implementations for integer primitive types as -1 represents None.
Required Associated Types§
Required Methods§
fn none() -> Self
fn some(v: Self::Inner) -> Self
fn is_none(&self) -> bool
fn inner(&self) -> Option<Self::Inner>
Provided Methods§
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.