Trait TryFrom

pub trait TryFrom<T>: Sized {
    type Error;

    // Required method
    fn try_from<'async_trait>(
        value: T,
    ) -> Pin<Box<dyn Future<Output = Result<Self, Self::Error>> + Send + 'async_trait>>
       where Self: 'async_trait;
}

Simple and safe type conversions that may fail in a controlled way under some circumstances. It is the reciprocal of TryInto.

This is useful when you are doing a type conversion that may trivially succeed but may also need special handling. For example, there is no way to convert an i64 into an i32 using the From trait, because an i64 may contain a value that an i32 cannot represent and so the conversion would lose data. This might be handled by truncating the i64 to an i32 (essentially giving the i64’s value modulo i32::MAX) or by simply returning i32::MAX, or by some other method. The From trait is intended for perfect conversions, so the TryFrom trait informs the programmer when a type conversion could go bad and lets them decide how to handle it.

Required Associated Types

type Error

The type returned in the event of a conversion error.

Required Methods

fn try_from<'async_trait>( value: T, ) -> Pin<Box<dyn Future<Output = Result<Self, Self::Error>> + Send + 'async_trait>>

where Self: 'async_trait,

Performs the conversion.

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.

Implementors