xerror

README

xerror

The xerror package provides advanced tools for working with errors in Go.

Features

• Const: Constant errors that can be declared at the package level without risk of modification.
• SentinelError: A wrapper that allows associating any error with a "marker" (sentinel) error, preserving the ability to check via errors.Is.

Installation

go get github.com/AleksandrGurkin/xerror

Usage

Const

Use xerror.Const to create immutable errors:

const ErrMyConstant = xerror.Const("my constant error")

func doSomething() error {
    return ErrMyConstant
}

SentinelError

Allows wrapping an error so it behaves like a sentinel but contains details:

var ErrNotFound = xerror.Const("not found")

func findUser(id string) error {
    err := db.Query(...)
    if err != nil {
        return xerror.WrapWithSentinel(err, ErrNotFound)
    }
    return nil
}

// Later:
if errors.Is(err, ErrNotFound) {
    // Will work
}

License

See the LICENSE file.

Documentation

Index

• func WrapWithSentinel(err error, sentinel error) error
• type Const
  • func (e Const) Error() string
• type SentinelError
  • func (e *SentinelError) Error() string
  • func (e *SentinelError) Is(target error) bool
  • func (e *SentinelError) Unwrap() error

Functions

func WrapWithSentinel

func WrapWithSentinel(err error, sentinel error) error

Types

type Const

type Const string

Const is used for constant sentinels

const Err1 = xerror.Const("const error")

func (Const) Error

func (e Const) Error() string

type SentinelError

type SentinelError struct {
	// contains filtered or unexported fields
}

func (*SentinelError) Error

func (e *SentinelError) Error() string

func (*SentinelError) Is

func (e *SentinelError) Is(target error) bool

func (*SentinelError) Unwrap

func (e *SentinelError) Unwrap() error