| // +build go1.13 |
| |
| package errors |
| |
| import ( |
| stderrors "errors" |
| ) |
| |
| // Is reports whether any error in err's chain matches target. |
| // |
| // The chain consists of err itself followed by the sequence of errors obtained by |
| // repeatedly calling Unwrap. |
| // |
| // An error is considered to match a target if it is equal to that target or if |
| // it implements a method Is(error) bool such that Is(target) returns true. |
| func Is(err, target error) bool { return stderrors.Is(err, target) } |
| |
| // As finds the first error in err's chain that matches target, and if so, sets |
| // target to that error value and returns true. |
| // |
| // The chain consists of err itself followed by the sequence of errors obtained by |
| // repeatedly calling Unwrap. |
| // |
| // An error matches target if the error's concrete value is assignable to the value |
| // pointed to by target, or if the error has a method As(interface{}) bool such that |
| // As(target) returns true. In the latter case, the As method is responsible for |
| // setting target. |
| // |
| // As will panic if target is not a non-nil pointer to either a type that implements |
| // error, or to any interface type. As returns false if err is nil. |
| func As(err error, target interface{}) bool { return stderrors.As(err, target) } |
| |
| // Unwrap returns the result of calling the Unwrap method on err, if err's |
| // type contains an Unwrap method returning error. |
| // Otherwise, Unwrap returns nil. |
| func Unwrap(err error) error { |
| return stderrors.Unwrap(err) |
| } |