Enum WindowError 

#[non_exhaustive]
pub enum WindowError {
    Os {
        operation: &'static str,
        source: Error,
    },
    OutOfBounds {
        at: u64,
        end: u64,
        len: u64,
    },
    TooLarge {
        wanted: usize,
        span: usize,
    },
}

What can go wrong when opening a window or moving it.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Os

The operating system refused a reservation, a mapping or a file operation.

Fields

operation: &'static str

Which step failed, so the error says where in the sequence it stopped.

source: Error

What the operating system said.

OutOfBounds

The requested range runs past the end of the file.

Fields

at: u64

Where the request started.

end: u64

One past where it ended.

len: u64

How long the file is.

TooLarge

The request cannot be covered by one view, so this window cannot serve it at all.

This is a configuration error rather than a data error: the window was opened with a span smaller than the largest range it was going to be asked for.

wanted can be larger than the length that was requested, and the difference is not a mistake. A view has to start on an alignment boundary, so a request that starts part of the way into one needs the bytes before it mapped as well, and wanted is what the mapping has to cover rather than what the caller asked to read.

Fields

wanted: usize

How many bytes a single view would have to cover, including alignment.

span: usize

How many the window can map at once.

Trait Implementations

impl Debug for WindowError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for WindowError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for WindowError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.