Macro anyerr

macro_rules! anyerr {
    ($fmt:literal$(, $($arg:expr),* $(,)?)?) => { ... };
    ($err:expr, $fmt:literal$(, $($arg:expr),* $(,)?)?) => { ... };
    ($err:expr) => { ... };
}

Converts a value into AnyError.

• anyerr!("msg") creates an error with just a message.
• anyerr!("this failed at {a} with {}", b) creates an error with a formatted message
• anyerr!(value) converts any impl StackError, impl std::error::Error, or impl Display into AnyError.
• anyerr!(value, "context") works as above and then adds context via AnyError::context.
• anyerr!(value, "context {}", foo) works as above, but with a formatted string as context

The forms that take value use autoref specialization to keep the most details possible: if given a StackError it uses AnyError::from_stack, if given a std error, uses AnyError::from_std, if given a value that impls Display it uses AnyError::from_display - in this order.