ex1.go

func ExtractStacktrace(err error) *Stacktrace {
	// https://github.com/pkg/errors

	// Packages definitions:
	// type Frame []uintptr
	// type StackTrace []Frame

	type stackTracer interface {
		StackTrace() errors.StackTrace
	}

	var pcs []uintptr
	if stacktrace, ok := err.(stackTracer); ok {
		// won't compile, as types differ - hard dependency
		pcs = stacktrace.StackTrace()
	}
	
	stacktrace := Stacktrace{
		Frames: extractFrames(pcs),
	}

	return &stacktrace
}

ex2.go

func ExtractStacktrace(err error) *Stacktrace {
	// https://github.com/pkg/errors

	// Packages definitions:
	// type Frame []uintptr
	// type StackTrace []Frame

	type stackTracer interface {
		StackTrace() errors.StackTrace
	}

	var pcs []uintptr
    if stacktrace, ok := err.(stackTracer); ok {
		// will compile, but requires type coercion - hard dependency
		st := stacktrace.StackTrace()

		for _, val := range st {
			pcs = append(pcs, uintptr(val))
		}
	}
	
	stacktrace := Stacktrace{
		Frames: extractFrames(pcs),
	}

	return &stacktrace
}

ex3.go

func ExtractStacktrace(err error) *Stacktrace {
	// https://github.com/pkg/errors

	// Packages definitions:
	// type Frame []uintptr
	// type StackTrace []Frame

	type stackTracer interface {
		StackTrace() []uintptr
	}

	var pcs []uintptr
	if stacktrace, ok := err.(stackTracer); ok {
		// won't read pcs, as interface is not satisfied - no dependency
		pcs = stacktrace.StackTrace()
	}
	
	stacktrace := Stacktrace{
		Frames: extractFrames(pcs),
	}

	return &stacktrace
}