flex-error

Use `E: Display + Debug` trait bound for `ErrorTracer<E>`

for eyre and anyhow tracers

• Use E: Display + Debug + Send + Sync + 'static trait bound for ErrorTracer<E> for eyre and anyhow tracers. The original E: std::error::Error + Send + Sync + 'static trait bound do not work well when individual crates have std features disabled, but had flex-error's std feature enabled somehow.

• Add into_detail and into_trace methods to error types defined by define_error!.
• Export local alias to std::error::Error so that std do not need to be available in user crate when define_error! is called.

• Make the Display implementation of error types use Debug to display error traces from eyre and other error tracers.

Breaking changes:

• The impl definition for std::error::Error is now generated based on whether the std feature is enabled on the flex-error crate, instead of the user crate that calls define_error.

Breaking changes:

• Define main error types in the form of struct Error(ErrorDetail, Trace) instead of the type alias type Error = ErrorReport<ErrorDetail, Trace>.

• Remove auto derive of common traits such as Clone and Eq for the main error type. Users can instead implement the traits explicitly since it is no longer a type alias.

• Change the error constructor convention from error::constructor_error() to error::Error::constructor().

• Allow multiple attributes to be given to main and sub errors in define_error!.

Breaking changes:

• Update structure of ErrorReport from ErrorReport { detail, trace } to ErrorReport(detail, trace) to allow simpler pattern matching.

• Auto derive common traits such as Clone and Eq for ErrorReport.

• Allow recursive error source using Self.

Breaking changes:

• Update define syntax from define_error!{ Error; ... } to define_error!{ Error { ... } }

• Allow custom derive attributes in the form of define_error!{ #[derive(Debug, ...)] Error { ... } }.

• Initial draft release for flex-error.