Annotate is used to add extra context to an existing error.

BadRequest error.

Cause returns the underlying cause of the error, if possible.

DeferredAnnotate annotates the given error (when it is not nil) with the given format string and arguments (like fmt.Sprintf).

IsErr reports whether err or any of the errors in its chain is equal to target.

New is a drop in replacement for the standard library errors module that records the location that the error is created.

NewWithAlert is a drop in replacement for the standard library errors module that records the location that the error is created but with alert msg for show.

ToError convert err to *err.

Trace add file and line info to err.

Wrap changes the code of the error.

conflict error.

miss token.

Error implements error interface and add Code, so errors with different message can be compared.

Errorer interface.

Locationer indicate where error occured.

Wrapper is an error implementation wrapping context around another error.