Trait ContextExt 

pub trait ContextExt<T>: Sized {
    // Required method
    fn with_context<C>(
        self,
        context: impl FnOnce() -> C,
    ) -> Result<T, BevyError>
       where C: Into<Cow<'static, str>>;

    // Provided method
    fn context<C>(self, context: C) -> Result<T, BevyError>
       where C: Into<Cow<'static, str>> { ... }
}

Extension methods for adding additional context messages to a BevyError

Required Methods

fn with_context<C>(self, context: impl FnOnce() -> C) -> Result<T, BevyError>

where C: Into<Cow<'static, str>>,

Annotate the error with a context message from a closure

Example

fn fallible() -> Result<(), BevyError> {
    let path = "some_file.txt";
    let _message = fs::read_to_string(path)
        .with_context(|| format!("failed to read {path}"))?;

    Ok(())
}

Provided Methods

fn context<C>(self, context: C) -> Result<T, BevyError>

where C: Into<Cow<'static, str>>,

Annotate the error with a context message.

Example

fn fallible() -> Result<(), BevyError> {
    // Produces a `BevyError` with the message
    // "failed to parse number: invalid digit found in string"
    let _parsed: usize = "I am not a number"
        .parse()
        .context("failed to parse number")?;

    Ok(())
}

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.

Implementations on Foreign Types

impl<T> ContextExt<T> for Option<T>

fn with_context<C>(self, context: impl FnOnce() -> C) -> Result<T, BevyError>

where C: Into<Cow<'static, str>>,

impl<T, E> ContextExt<T> for Result<T, E>

where E: Into<BevyError>,

fn with_context<C>(self, context: impl FnOnce() -> C) -> Result<T, BevyError>

where C: Into<Cow<'static, str>>,

Implementors