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errors

package module

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Versions in this module

v1

v1.3.0

Apr 18, 2026

Changes in this version

+ var ErrLimitReached = Const("limit_reached", "error collection limit reached")

+ func AsType[T error](err error) (T, bool)

+ func Collect(ctx context.Context, ch <-chan error, n int) error

+ func Contains(err error, targets ...error) bool

+ func Drain(ch <-chan error) error

+ func Fan(ctx context.Context, chans ...<-chan error) <-chan error

+ func Filter[T error](err error) []T

+ func FindType[T error](err error, predicate func(T) bool) (T, bool)

+ func First(ctx context.Context, ch <-chan error) error

+ func FirstOfType[T error](err error) (T, bool)

+ func HTTPError(w http.ResponseWriter, err error, opts ...HTTPOption)

+ func HTTPStatusCode(err error, defaultCode int) int

+ func IsType[T error](err error) bool

+ func Join(errs ...error) error

+ func JoinErrors(errs []error, keyValues ...interface{}) error

+ func Map[T error, R any](err error, fn func(T) R) []R

+ func Reduce[T error, R any](err error, initial R, fn func(T, R) R) R

type Chain

+ func (c *Chain) StepCtx(fn func(ctx context.Context) error) *Chain

type Error

+ func (e *Error) LogValue() slog.Value

+ type Group struct

+ func NewGroup(opts ...GroupOption) *Group

+ func (g *Group) Errors() []error

+ func (g *Group) Go(fn func() error)

+ func (g *Group) GoCtx(fn func(ctx context.Context) error)

+ func (g *Group) Wait() error

+ type GroupOption func(*Group)

+ func GroupWithContext(ctx context.Context, cancelOnFirst bool) GroupOption

+ func GroupWithLimit(n int) GroupOption

+ type HTTPOption func(*httpConfig)

+ func WithBody(include bool) HTTPOption

+ func WithBodyFunc(fn func(error) string) HTTPOption

+ func WithFallbackCode(code int) HTTPOption

+ type InspectOption func(*inspectConfig)

+ func WithMaxDepth(n int) InspectOption

+ func WithStackFrames(n int) InspectOption

+ type Sentinel struct

+ func Const(name, msg string) *Sentinel

+ func (s *Sentinel) As(target any) bool

+ func (s *Sentinel) Error() string

+ func (s *Sentinel) Is(target error) bool

+ func (s *Sentinel) LogValue() slog.Value

+ func (s *Sentinel) MarshalJSON() ([]byte, error)

+ func (s *Sentinel) Name() string

+ func (s *Sentinel) String() string

+ func (s *Sentinel) Unwrap() error

+ func (s *Sentinel) With(msg string) *Error

+ type Stream struct

+ func NewStream[T any](ctx context.Context, items []T, fn func(T) error, workers ...int) *Stream[T]

+ func (s *Stream[T]) Each(fn func(error))

+ func (s *Stream[T]) Stop()

+ func (s *Stream[T]) Wait() error

v1.2.0

Jan 19, 2026

Changes in this version

type Error

+ func Err(msg string, err error) *Error

v1.1.0

May 6, 2025

Changes in this version

+ const DefaultCode

+ func As(err error, target interface{}) bool

+ func Caller(skip int) (file string, line int, function string)

+ func Category(err error) string

+ func Code(err error) int

+ func Configure(cfg Config)

+ func Context(err error) map[string]interface

+ func Count(err error) uint64

+ func ExecuteReply[T any](r *Retry, fn func() (T, error)) (T, error)

+ func Find(err error, pred func(error) bool) error

+ func FmtErrorCheck(format string, args ...interface{}) (result string, err error)

+ func FormatError(err error) string

+ func Has(err error) bool

+ func HasContextKey(err error, key string) bool

+ func Inspect(err error)

+ func InspectError(err *Error)

+ func Is(err, target error) bool

+ func IsEmpty(err error) bool

+ func IsError(err error) bool

+ func IsNull(err error) bool

+ func IsRetryable(err error) bool

+ func IsTimeout(err error) bool

+ func Name(err error) string

+ func Stack(err error) []string

+ func Std(text string) error

+ func Stdf(format string, a ...interface{}) error

+ func Unwrap(err error) error

+ func UnwrapAll(err error) []error

+ func Walk(err error, fn func(error))

+ func WarmPool(count int)

+ func WarmStackPool(count int)

+ func With(err error, key string, value interface{}) error

+ type BackoffStrategy interface

+ Backoff func(attempt int, baseDelay time.Duration) time.Duration

+ type Chain struct

+ func NewChain(opts ...ChainOption) *Chain

+ func (c *Chain) Call(fn interface{}, args ...interface{}) *Chain

+ func (c *Chain) Code(code int) *Chain

+ func (c *Chain) Errors() []error

+ func (c *Chain) HasErrors() bool

+ func (c *Chain) LastError() error

+ func (c *Chain) Len() int

+ func (c *Chain) LogOnFail() *Chain

+ func (c *Chain) MaxErrors(max int) *Chain

+ func (c *Chain) Optional() *Chain

+ func (c *Chain) Reset()

+ func (c *Chain) Retry(maxAttempts int, delay time.Duration, opts ...RetryOption) *Chain

+ func (c *Chain) Run() error

+ func (c *Chain) RunAll() error

+ func (c *Chain) Step(fn func() error) *Chain

+ func (c *Chain) Tag(category ErrorCategory) *Chain

+ func (c *Chain) Timeout(d time.Duration) *Chain

+ func (c *Chain) Unwrap() []error

+ func (c *Chain) With(key string, value interface{}) *Chain

+ func (c *Chain) WithLog(attrs ...slog.Attr) *Chain

+ type ChainOption func(*Chain)

+ func ChainWithAutoWrap(auto bool) ChainOption

+ func ChainWithLogHandler(handler slog.Handler) ChainOption

+ func ChainWithMaxErrors(max int) ChainOption

+ func ChainWithTimeout(d time.Duration) ChainOption

+ type Config struct

+ AutoFree bool

+ ContextSize int

+ DisablePooling bool

+ FilterInternal bool

+ StackDepth int

+ type ConstantBackoff struct

+ func (c ConstantBackoff) Backoff(_ int, baseDelay time.Duration) time.Duration

+ type Error struct

+ func Convert(err error) *Error

+ func Empty() *Error

+ func Errorf(format string, args ...interface{}) *Error

+ func From(err error) *Error

+ func FromContext(ctx context.Context, err error) *Error

+ func Merge(errs ...error) *Error

+ func Named(name string) *Error

+ func New(text string) *Error

+ func Newf(format string, args ...interface{}) *Error

+ func Trace(text string) *Error

+ func Tracef(format string, args ...interface{}) *Error

+ func Transform(err error, fn func(*Error)) *Error

+ func WithStack(err error) *Error

+ func Wrap(err error, wrapper *Error) *Error

+ func Wrapf(err error, format string, args ...interface{}) *Error

+ func (e *Error) As(target interface{}) bool

+ func (e *Error) Callback(fn func()) *Error

+ func (e *Error) Category() string

+ func (e *Error) Code() int

+ func (e *Error) Context() map[string]interface{}

+ func (e *Error) Copy() *Error

+ func (e *Error) Count() uint64

+ func (e *Error) Err() error

+ func (e *Error) Error() string

+ func (e *Error) FastStack() []string

+ func (e *Error) Find(pred func(error) bool) error

+ func (e *Error) Format() string

+ func (e *Error) Free()

+ func (e *Error) Has() bool

+ func (e *Error) HasContextKey(key string) bool

+ func (e *Error) Increment() *Error

+ func (e *Error) Is(target error) bool

+ func (e *Error) IsEmpty() bool

+ func (e *Error) IsNull() bool

+ func (e *Error) MarshalJSON() ([]byte, error)

+ func (e *Error) Msgf(format string, args ...interface{}) *Error

+ func (e *Error) Name() string

+ func (e *Error) Reset()

+ func (e *Error) Stack() []string

+ func (e *Error) Trace() *Error

+ func (e *Error) Transform(fn func(*Error)) *Error

+ func (e *Error) Unwrap() error

+ func (e *Error) UnwrapAll() []error

+ func (e *Error) Walk(fn func(error))

+ func (e *Error) With(keyValues ...interface{}) *Error

+ func (e *Error) WithCategory(category ErrorCategory) *Error

+ func (e *Error) WithCode(code int) *Error

+ func (e *Error) WithName(name string) *Error

+ func (e *Error) WithRetryable() *Error

+ func (e *Error) WithStack() *Error

+ func (e *Error) WithTemplate(template string) *Error

+ func (e *Error) WithTimeout() *Error

+ func (e *Error) Wrap(cause error) *Error

+ func (e *Error) WrapNotNil(cause error) *Error

+ func (e *Error) Wrapf(cause error, format string, args ...interface{}) *Error

+ type ErrorCategory string

+ type ErrorFormatter func([]error) string

+ type ErrorOpts struct

+ SkipStack int

+ type ErrorPool struct

+ func NewErrorPool() *ErrorPool

+ func (ep *ErrorPool) Get() *Error

+ func (ep *ErrorPool) Put(e *Error)

+ func (ep *ErrorPool) Stats() (hits, misses int64)

+ type ExponentialBackoff struct

+ func (e ExponentialBackoff) Backoff(attempt int, baseDelay time.Duration) time.Duration

+ type LinearBackoff struct

+ func (l LinearBackoff) Backoff(attempt int, baseDelay time.Duration) time.Duration

+ type MultiError struct

+ func NewMultiError(opts ...MultiErrorOption) *MultiError

+ func (m *MultiError) Add(errs ...error)

+ func (m *MultiError) Addf(format string, args ...interface{})

+ func (m *MultiError) Clear()

+ func (m *MultiError) Count() int

+ func (m *MultiError) Error() string

+ func (m *MultiError) Errors() []error

+ func (m *MultiError) Filter(fn func(error) bool) *MultiError

+ func (m *MultiError) First() error

+ func (m *MultiError) Has() bool

+ func (m *MultiError) IsNull() bool

+ func (m *MultiError) Last() error

+ func (m *MultiError) MarshalJSON() ([]byte, error)

+ func (m *MultiError) Merge(other *MultiError)

+ func (m *MultiError) Single() error

+ func (m *MultiError) String() string

+ func (m *MultiError) Unwrap() []error

+ type MultiErrorOption func(*MultiError)

+ func WithFormatter(f ErrorFormatter) MultiErrorOption

+ func WithLimit(n int) MultiErrorOption

+ func WithRand(r *rand.Rand) MultiErrorOption

+ func WithSampling(rate uint32) MultiErrorOption

+ type Retry struct

+ func NewRetry(options ...RetryOption) *Retry

+ func (r *Retry) Attempts() int

+ func (r *Retry) Execute(fn func() error) error

+ func (r *Retry) ExecuteContext(ctx context.Context, fn func() error) error

+ func (r *Retry) Transform(opts ...RetryOption) *Retry

+ type RetryOption func(*Retry)

+ func WithBackoff(strategy BackoffStrategy) RetryOption

+ func WithContext(ctx context.Context) RetryOption

+ func WithDelay(delay time.Duration) RetryOption

+ func WithJitter(jitter bool) RetryOption

+ func WithMaxAttempts(maxAttempts int) RetryOption

+ func WithMaxDelay(maxDelay time.Duration) RetryOption

+ func WithOnRetry(onRetry func(attempt int, err error)) RetryOption

+ func WithRetryIf(retryIf func(error) bool) RetryOption