A very simple mechanism for controlling tracing in Go is to use global bool variables:

var Trace bool

func foo() {
	if Trace {
		fmt.Printf("foo\n")
	}
}

initialization

This package just provides a mechanism to initialize such Trace variables:

	var flags trace.Flags
	flags.Trace = "a"  // use a command-line option to set this
	
	err := t.Flags.Set(
		trace.T("a", &TraceA),
		trace.T("b", &TraceB),
	)
	// sets TraceA to true

The trace package has no dependencies to other packages, but the trace.Flags struct can be used with the melato.org/command package (via reflection), as shown in example.go.

melato/trace

initialization