Enum Error

#[non_exhaustive]
pub enum Error {
    SwStart,
    SwStop,
    SwGuard,
    GuardNew,
}

Enumeration over possible errors.

Display implementation

Error implements Display by explaining what happened and what was expected instead.

The exact text of these explanations is not stable and should not be relied upon.

let error = Error::SwStart;
assert_eq!(
    error.to_string(),
    "started stopwatch while running, but expected stopped"
);

Feature flags

When the std feature is enabled, Error implements std::error::Error.

When the nightly feature is enabled and the std feature is not enabled, Error implements core::error::Error. This requires a nightly compiler.

Examples

let mut sw = Sw::new_started();
assert_eq!(sw.start(), Err(Error::SwStart));
sw.stop()?;
assert_eq!(sw.stop(), Err(Error::SwStop));

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.

SwStart

Returned by methods that start the stopwatch. Expects that it’s stopped.

SwStop

Returned by methods that stop the stopwatch. Expects that it’s running.

SwGuard

Returned by methods that guard the stopwatch. Expects that it’s stopped.

GuardNew

Returned by Guard::new. Expects that it’s running.

Implementations

impl Error

pub const fn expects_running(&self) -> bool

Returns true if the stopwatch was expected to be running.

Examples

assert!(Error::SwStop.expects_running());
assert!(Error::GuardNew.expects_running());

pub const fn expects_stopped(&self) -> bool

Returns true if the stopwatch was expected to be stopped.

Examples

assert!(Error::SwStart.expects_stopped());
assert!(Error::SwGuard.expects_stopped());

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

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.

impl Hash for Error

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Error

fn eq(&self, other: &Error) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Error

impl Eq for Error

impl StructuralPartialEq for Error