Trait rubbl_core::io::OpenResultExt

pub trait OpenResultExt {
    type Reprocessed;
    fn require_found(self) -> Self::Reprocessed;
}

This is an extension trait that makes it more convenient to handle errors when opening files that may be missing.

Various parts of Rubbl try to open files but don’t mind if the files are missing. This is expressed using return types like Result<Option<File>>: if the value is Ok(None), that means that the file was not found, even though the underlying I/O operation probably return an Err type.

There are times when we want to use these APIs, but it actually is an error if the file in question is missing. This trait provides a require_found method on the Result<Option<T>> type that removes the Option layer of the type, converting Ok(None) into an Err containing a NotFound error.

Associated Types

type Reprocessed

The output type of the require_found method.

Result<Option<T>> becomes Result<T>. Due to the way the trait is specified, we have to use an associated type to express this fact.

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Required methods

fn require_found(self) -> Self::Reprocessed

If self is Ok(None), convert it into an Err with a NotFound type.

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Implementations on Foreign Types

impl<T, E> OpenResultExt for Result<Option<T>, E> where
    E: From<Error>, 

type Reprocessed = Result<T, E>

fn require_found(self) -> Self::Reprocessed

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Implementors

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