cppintf: with param

_demo/cppintf/cppintf.go

@@ -3,23 +3,23 @@ package main
 import (
 	"github.com/goplus/llgo/_demo/cppintf/foo"
 	"github.com/goplus/llgo/c"
+	"github.com/goplus/llgo/c/math"
 )
 
 type Bar struct {
 	foo.Callback
 	a int
-	b float64
 }
 
-func NewBar(a int, b float64) *Bar {
+func NewBar(a int) *Bar {
 	return &Bar{
 		Callback: foo.Callback{
 			Vptr: &foo.CallbackVtbl{
-				ValA: c.Func((*Bar).getA),
+				Val:  c.Func((*Bar).getA),
-				ValB: c.Func((*Bar).getB),
+				Calc: c.Func((*Bar).sqrt),
 			},
 		},
-		a: a, b: b,
+		a: a,
 	}
 }
 
@@ -27,11 +27,11 @@ func (p *Bar) getA() int {
 	return p.a
 }
 
-func (p *Bar) getB() float64 {
+func (p *Bar) sqrt(v float64) float64 {
-	return p.b
+	return math.Sqrt(v)
 }
 
 func main() {
-	bar := NewBar(1, 2.0)
+	bar := NewBar(1)
 	foo.F(&bar.Callback)
 }

_demo/cppintf/foo/bar/bar.cpp

@@ -2,10 +2,10 @@
 #define interface struct
 
 interface ICallback {
-	virtual int valA() = 0;
+	virtual int val() = 0;
-	virtual double valB() = 0;
+	virtual double calc(double v) = 0;
 };
 
 extern "C" void f(ICallback* cb) {
-	printf("Hello %d, %lf!\n", cb->valA(), cb->valB());
+	printf("val: %d\ncalc(2): %lf\n", cb->val(), cb->calc(2));
 }

_demo/cppintf/foo/foo.go

@@ -14,8 +14,8 @@ type Callback struct {
 }
 
 type CallbackVtbl struct {
-	ValA unsafe.Pointer
+	Val  unsafe.Pointer
-	ValB unsafe.Pointer
+	Calc unsafe.Pointer
 }
 
 //go:linkname F C.f