qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-27 02:21:17 -07:00
Code Releases Activity

errors: clarify doc for As

Browse Source 
Change-Id: I389d140e8fd2849e4dc438246add47819f6b25a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/181300
Reviewed-by: Bryan C. Mills <bcmills@google.com>
This commit is contained in:
Jonathan Amsterdam 2019-06-08 07:43:40 -04:00
parent bdd4201552
commit f2a4c139c1
1 changed files with 9 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
src/errors/wrap.go
View File

@ -47,15 +47,16 @@ func Is(err, target error) bool {
}
}
// As finds the first error in err's chain that matches the type to which target
// points, and if so, sets the target to its value and returns true. An error
// matches a type if it is assignable to the target type, or if it has a method
// As(interface{}) bool such that As(target) returns true. As will panic if
// target is not a non-nil pointer to a type which implements error or is of
// interface type. As returns false if 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.
//
// The As method should set the target to its value and return true if err
// matches the type to which target points.
// 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 {
if target == nil {
panic("errors: target cannot be nil")