Trait NotFound 

pub trait NotFound<T> {
    // Required methods
    fn is_not_found(&self) -> bool;
    fn optional(self) -> Result<Option<T>>;
}

Classifies and adapts results carrying the crate’s not-found error family.

Successful results and unrelated errors are not classified as missing, and only a not-found error converts to an absent value. Classification delegates to Error::is_not_found.

Required Methods

fn is_not_found(&self) -> bool

Reports whether the result contains a not-found error.

An Ok value always returns false. Other error variants also return false without changing the result.

fn optional(self) -> Result<Option<T>>

Converts a not-found error into an absent value.

An Ok value is wrapped in Some and a not-found error becomes Ok(None), so a caller distinguishes an absent value from a failed operation. Every other error is returned unchanged.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<T> NotFound<T> for Result<T, Error>