Annotate annotates the error with the message, unless the error is nil.

As finds the first error in err's chain that matches target, and if so, sets target to that error value and returns true.

Check is a simple error-checking helper that panics if err is not nil.

FromRecovered checks if v, which should be a value returned by recover) is an error and, if it isn't, wraps it using [fmt.Errorf].

Is reports whether any error in err's chain matches target.

Join returns an error that wraps the given errors.

Must is a helper that wraps a call to a function returning (T, error) and panics if the error is non-nil.

New returns an error that formats as the given msg.

Unwrap returns the result of calling the Unwrap method on err, if err's type contains an Unwrap method returning error.

WithDeferred is a helper function for deferred errors.

ErrBadEnumValue indicates that the provided value is not a valid value within an enumeration of types (a sum type) or values.

ErrDuplicated indicates that a value that should be unique is duplicated.

ErrEmptyValue indicates that a value is provided but it is empty.

ErrNegative indicates that the provided value is negative when it should be greater than or equal to zero.

ErrNotEmpty indicates that a value that must be empty isn't.

ErrNotPositive indicates that the provided value is negative or zero when it should be greater than zero.

ErrNoValue indicates that a required value has not been provided.

ErrOutOfRange indicates that provided value is outside of a valid range of ordered values.

ErrUnsupported indicates that a requested operation cannot be performed, because it is unsupported.

Pair is a pair of errors.

Aser is a copy of the hidden aser interface from the Go standard library.

Deferred is the interface for errors that were returned by cleanup functions, such as Close.

Iser is a copy of the hidden iser interface from the Go standard library.

Wrapper is a copy of the hidden wrapper interface from the Go standard library.

WrapperSlice is a copy of the hidden wrapper interface added to the Go standard library in Go 1.20.

Error is the constant error type.