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

Cause calls Unwrap on each error it finds.

Errorf formats according to a format specifier and returns the string as a value that satisfies error.

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

Join returns an error that wraps the given errors.

New returns an error that formats as the given text.

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

WithMessage annotates err with a new message.

WithMessagef annotates err with the format specifier.

Wrap is an alias for WithMessage.

Wrapf is an alias for WithMessagef.

MultiError is an error that wraps multiple errors.