Stdnull added

Author: lainio

err2.go

@@ -33,6 +33,11 @@ var (
 	// same error. These error are mainly for that purpose.
 	ErrNotRecoverable = errors.New("cannot recover")
 	ErrRecoverable    = errors.New("recoverable")
+
+	// Stdnull is helper variable for io.Writer need e.g. err2.SetLogTracer in
+	// cases you don't want to use automatic log writer, i.e. LogTracer == nil.
+	// It's usually used to change how the Catch works, e.g., in CLI apps.
+	Stdnull = &nullDev{}
 )
 
 // Handle is the general purpose error handling function. What makes it so
@@ -116,7 +121,11 @@ func Handle(err *error, a ...any) {
 //
 // The preceding line catches the errors and panics and prints an annotated
 // error message about the error source (from where the error was thrown) to the
-// currently set log.
+// currently set log. Note, when log stream isn't set, the standard log is used.
+// It can be bound to, e.g., glog. And if you want to suppress automatic logging
+// use the following setup:
+//
+//	err2.SetLogTracer(err2.Stdnull)
 //
 // The next one stops errors and panics, but allows you handle errors, like
 // cleanups, etc. The error handler function has same signature as Handle's
@@ -228,6 +237,10 @@ func Err(f func(err error)) func(error) error {
 	}
 }
 
+type nullDev struct{}
+
+func (nullDev) Write([]byte) (int, error) { return 0, nil }
+
 func doTrace(err error) {
 	if err == nil || err.Error() == "" {
 		return