Drop-in replacement for the standard library errors package and github.com/pkg/errors
Drop-in replacement for the standard library errors
package and github.com/pkg/errors.
This is a single, lightweight library merging the features of standard library errors
package
and github.com/pkg/errors. It also backports a few features
(like Go 1.13 error handling related features).
Standard library features:
New
creates an error with stack traceUnwrap
supports both Go 1.13 wrapper (interface { Unwrap() error }
) and pkg/errors causer (interface { Cause() error }
) interfaceIs
and As
functionsgithub.com/pkg/errors features:
New
, Errorf
, WithMessage
, WithMessagef
, WithStack
, Wrap
, Wrapf
functions behave the same way as in the original libraryCause
supports both Go 1.13 wrapper (interface { Unwrap() error }
) and pkg/errors causer (interface { Cause() error }
) interfaceAdditional features:
NewPlain
creates a new error without any attached context, like stack traceSentinel
is a shorthand type for creating constant error
WithStackDepth
allows attaching stack trace with a custom caller depthWithStackDepthIf
, WithStackIf
, WrapIf
, WrapIff
only annotate errors with a stack trace if there isn't one already in the error chainNewWithDetails
, WithDetails
and Wrap*WithDetails
functions to add key-value pairs to an errormatch
packagego get emperror.dev/errors
package main
import "emperror.dev/errors"
// ErrSomethingWentWrong is a sentinel error which can be useful within a single API layer.
const ErrSomethingWentWrong = errors.Sentinel("something went wrong")
// ErrMyError is an error that can be returned from a public API.
type ErrMyError struct {
Msg string
}
func (e ErrMyError) Error() string {
return e.Msg
}
func foo() error {
// Attach stack trace to the sentinel error.
return errors.WithStack(ErrSomethingWentWrong)
}
func bar() error {
return errors.Wrap(ErrMyError{"something went wrong"}, "error")
}
func main() {
if err := foo(); err != nil {
if errors.Cause(err) == ErrSomethingWentWrong { // or errors.Is(ErrSomethingWentWrong)
// handle error
}
}
if err := bar(); err != nil {
if errors.As(err, &ErrMyError{}) {
// handle error
}
}
}
Match errors:
package main
import (
"emperror.dev/errors"
"emperror.dev/errors/match"
)
// ErrSomethingWentWrong is a sentinel error which can be useful within a single API layer.
const ErrSomethingWentWrong = errors.Sentinel("something went wrong")
type clientError interface{
ClientError() bool
}
func foo() error {
// Attach stack trace to the sentinel error.
return errors.WithStack(ErrSomethingWentWrong)
}
func main() {
var ce clientError
matcher := match.Any{match.As(&ce), match.Is(ErrSomethingWentWrong)}
if err := foo(); err != nil {
if matcher.MatchError(err) {
// you can use matchers to write complex conditions for handling (or not) an error
// used in emperror
}
}
}
Contributions are welcome! :)
./pleasew build
./pleasew test
./pleasew gotest
./pleasew lint
The MIT License (MIT). Please see License File for more information.
Certain parts of this library are inspired by (or entirely copied from) various third party libraries. Their licenses can be found in the Third Party License File.