pkg errors, var ErrUnsupported error #41198
pkg flag, func BoolFunc(string, string, func(string) error) #53747
pkg flag, method (*FlagSet) BoolFunc(string, string, func(string) error) #53747
pkg go/ast, func IsGenerated(*File) bool #28089
pkg go/ast, func NewPackage //deprecated #52463
pkg go/ast, type File struct, GoVersion string #59033
pkg go/ast, type Importer //deprecated #52463
pkg go/ast, type Object //deprecated #52463