Trait frame_support::traits::defensive_prelude::DefensiveResult

pub trait DefensiveResult<T, E> {
    // Required methods
    fn defensive_map_err<F, O: FnOnce(E) -> F>(self, o: O) -> Result<T, F>;
    fn defensive_map_or_else<U, D: FnOnce(E) -> U, F: FnOnce(T) -> U>(
        self,
        default: D,
        f: F
    ) -> U;
    fn defensive_ok(self) -> Option<T>;
    fn defensive_map<U, F: FnOnce(T) -> U>(self, f: F) -> Result<U, E>;
}

Subset of methods similar to Defensive that can only work for a Result.

Required Methods

fn defensive_map_err<F, O: FnOnce(E) -> F>(self, o: O) -> Result<T, F>

Defensively map the error into another return type, but you are really sure that this conversion should never be needed.

fn defensive_map_or_else<U, D: FnOnce(E) -> U, F: FnOnce(T) -> U>( self, default: D, f: F ) -> U

Defensively map and unpack the value to something else (U), or call the default callback if Err, which should never happen.

fn defensive_ok(self) -> Option<T>

Defensively transform this result into an option, discarding the Err variant if it happens, which should never happen.

fn defensive_map<U, F: FnOnce(T) -> U>(self, f: F) -> Result<U, E>

Exactly the same as map, but it prints the appropriate warnings if the value being mapped is Err.

Implementors

impl<T, E: Debug> DefensiveResult<T, E> for Result<T, E>