blob: 4f99bfc6d473586563fc7158717af088fb4024a6 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
|
package example
// FooBarGo is a superset of FooBarAbstract and hence FooBarGo can be used as a
// drop in replacement for FooBarAbstract but the reverse causes a compile time
// error.
type FooBarGo interface {
FooBarAbstract
deleteFooBarAbstract()
IsFooBarGo()
}
// Via embedding fooBarGo "inherits" all methods of FooBarAbstract.
type fooBarGo struct {
FooBarAbstract
}
func (fbgs *fooBarGo) deleteFooBarAbstract() {
DeleteDirectorFooBarAbstract(fbgs.FooBarAbstract)
}
// The IsFooBarGo method ensures that FooBarGo is a superset of FooBarAbstract.
// This is also how the class hierarchy gets represented by the SWIG generated
// wrapper code. For an instance FooBarCpp has the IsFooBarAbstract and
// IsFooBarCpp methods.
func (fbgs *fooBarGo) IsFooBarGo() {}
// Go type that defines the DirectorInterface. It contains the Foo and Bar
// methods that overwrite the respective virtual C++ methods on FooBarAbstract.
type overwrittenMethodsOnFooBarAbstract struct {
// Backlink to FooBarAbstract so that the rest of the class can be used by
// the overridden methods.
fb FooBarAbstract
// If additional constructor arguments have been given they are typically
// stored here so that the overriden methods can use them.
}
func (om *overwrittenMethodsOnFooBarAbstract) Foo() string {
// DirectorFooBarAbstractFoo calls the base method FooBarAbstract::Foo.
return "Go " + DirectorFooBarAbstractFoo(om.fb)
}
func (om *overwrittenMethodsOnFooBarAbstract) Bar() string {
return "Go Bar"
}
func NewFooBarGo() FooBarGo {
// Instantiate FooBarAbstract with selected methods overridden. The methods
// that will be overwritten are defined on
// overwrittenMethodsOnFooBarAbstract and have a compatible signature to the
// respective virtual C++ methods. Furthermore additional constructor
// arguments will be typically stored in the
// overwrittenMethodsOnFooBarAbstract struct.
om := &overwrittenMethodsOnFooBarAbstract{}
fb := NewDirectorFooBarAbstract(om)
om.fb = fb // Backlink causes cycle as fb.v = om!
fbgs := &fooBarGo{FooBarAbstract: fb}
// The memory of the FooBarAbstract director object instance can be
// automatically freed once the FooBarGo instance is garbage collected by
// uncommenting the following line. Please make sure to understand the
// runtime.SetFinalizer specific gotchas before doing this. Furthemore
// DeleteFooBarGo should be deleted if a finalizer is in use or the fooBarGo
// struct needs additional data to prevent double deletion.
// runtime.SetFinalizer(fbgs, FooBarGo.deleteFooBarAbstract)
return fbgs
}
// Recommended to be removed if runtime.SetFinalizer is in use.
func DeleteFooBarGo(fbg FooBarGo) {
fbg.deleteFooBarAbstract()
}
|
