-
Notifications
You must be signed in to change notification settings - Fork 5
/
class.go
309 lines (253 loc) · 6.22 KB
/
class.go
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
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
package exec
import (
"errors"
"fmt"
"reflect"
"strings"
qlang "github.com/xushiwei/qlang/spec"
)
var (
// ErrNewWithoutClassName is returned when new doesn't specify a class.
ErrNewWithoutClassName = errors.New("new object without class name")
// ErrNewObjectWithNotType is returned when new T but T is not a type.
ErrNewObjectWithNotType = errors.New("can't new object: not a type")
// ErrRefWithoutObject is returned when refer member without specified an object.
ErrRefWithoutObject = errors.New("reference without object")
)
// -----------------------------------------------------------------------------
// A Class represents a qlang class.
//
type Class struct {
Fns map[string]*Function
Ctx *Context
}
// Exec is required by interface Instr.
//
func (p *Class) Exec(stk *Stack, ctx *Context) {
p.Ctx = ctx
for _, f := range p.Fns {
f.Parent = ctx
}
stk.Push(p)
}
// GoType returns the underlying go type. required by `qlang type` spec.
//
func (p *Class) GoType() reflect.Type {
return typeIntf
}
// NewInstance creates a new instance of a qlang type. required by `qlang type` spec.
//
func (p *Class) NewInstance(stk *Stack, args ...interface{}) interface{} {
return p.New(stk, args...)
}
// New creates a new instance of this class.
//
func (p *Class) New(stk *Stack, args ...interface{}) *Object {
obj := &Object{
vars: make(map[string]interface{}),
Cls: p,
}
if init, ok := p.Fns["_init"]; ok { // 构造函数
closure := &Method{
this: obj,
fn: init,
}
closure.Call(stk, args...)
} else if len(args) > 0 {
panic("constructor `_init` not found")
}
return obj
}
// IClass returns a Class instruction.
//
func IClass() *Class {
fns := make(map[string]*Function)
return &Class{Fns: fns}
}
// -----------------------------------------------------------------------------
// A Object represents a qlang object.
//
type Object struct {
vars map[string]interface{}
Cls *Class
}
// Vars returns all variables (not including methods) of this object.
//
func (p *Object) Vars() map[string]interface{} {
return p.vars
}
// SetVar sets the value of a qlang object's member.
//
func (p *Object) SetVar(name string, val interface{}) {
if _, ok := p.Cls.Fns[name]; ok {
panic("set failed: class already have a method named " + name)
}
p.vars[name] = val
}
// Member returns a member of this object.
//
func (p *Object) Member(name string) interface{} {
if val, ok := p.vars[name]; ok {
return val
}
if fn, ok := p.Cls.Fns[name]; ok {
return &Method{
this: p,
fn: fn,
}
}
panic(fmt.Errorf("object doesn't has member `%s`", name))
}
// GetMemberVar implements get(object, key).
//
func GetMemberVar(m interface{}, key interface{}) interface{} {
if v, ok := m.(*Object); ok {
if name, ok := key.(string); ok {
return v.Member(name)
}
panic("get(object, member): member should be `string` type")
}
panic(fmt.Sprintf("type `%v` doesn't support `get` operator", reflect.TypeOf(m)))
}
func init() {
qlang.GetEx = GetMemberVar
}
// -----------------------------------------------------------------------------
// A Method represents a method of an Object.
//
type Method struct {
this *Object
fn *Function
}
// Call calls this method with arguments.
//
func (p *Method) Call(stk *Stack, a ...interface{}) interface{} {
args := make([]interface{}, len(a)+1)
args[0] = p.this
for i, v := range a {
args[i+1] = v
}
return p.fn.Call(stk, args...)
}
// -----------------------------------------------------------------------------
type newTyper interface {
NewInstance(args ...interface{}) interface{}
}
type newTyperEx interface {
NewInstance(stk *Stack, args ...interface{}) interface{}
}
type iNew int
func (nArgs iNew) Exec(stk *Stack, ctx *Context) {
var args []interface{}
if nArgs != 0 {
args = stk.PopNArgs(int(nArgs))
}
if v, ok := stk.Pop(); ok {
if cls, ok := v.(newTyperEx); ok {
obj := cls.NewInstance(stk, args...)
stk.Push(obj)
return
}
if cls, ok := v.(newTyper); ok {
obj := cls.NewInstance(args...)
stk.Push(obj)
return
}
panic(ErrNewObjectWithNotType)
}
panic(ErrNewWithoutClassName)
}
// INew returns a New instruction.
//
func INew(nArgs int) Instr {
return iNew(nArgs)
}
// -----------------------------------------------------------------------------
type iMemberRef struct {
name string
}
var (
typeObjectPtr = reflect.TypeOf((*Object)(nil))
typeClassPtr = reflect.TypeOf((*Class)(nil))
)
func (p *iMemberRef) Exec(stk *Stack, ctx *Context) {
v, ok := stk.Pop()
if !ok {
panic(ErrRefWithoutObject)
}
name := p.name
t := reflect.TypeOf(v)
switch t {
case typeObjectPtr:
val := v.(*Object).Member(name)
stk.Push(val)
return
case typeClassPtr:
o := v.(*Class)
val, ok := o.Fns[name]
if !ok {
panic(fmt.Errorf("class doesn't has method `%s`", name))
}
stk.Push(val)
return
}
obj := reflect.ValueOf(v)
kind := obj.Kind()
switch {
case kind == reflect.Map:
m := obj.MapIndex(reflect.ValueOf(name))
if m.IsValid() {
stk.Push(m.Interface())
} else {
panic(fmt.Errorf("member `%s` not found", name))
}
default:
name = strings.Title(name)
m := obj.MethodByName(name)
if !m.IsValid() {
if kind == reflect.Ptr {
obj = reflect.Indirect(obj)
m = obj.FieldByName(name)
} else if obj.CanAddr() {
obj = obj.Addr()
m = obj.MethodByName(name)
}
if !m.IsValid() {
panic(fmt.Errorf("type `%v` doesn't has member `%s`", reflect.TypeOf(v), name))
}
t = obj.Type()
}
if qlang.AutoCall[t] && m.Type().NumIn() == 0 {
out := m.Call(nil)
stk.PushRet(out)
return
}
stk.Push(m.Interface())
}
}
func (p *iMemberRef) ToVar() Instr {
return &iMemberVar{p.name}
}
// MemberRef returns a MemberRef instruction.
//
func MemberRef(name string) Instr {
return &iMemberRef{name}
}
// -----------------------------------------------------------------------------
// MemberVar
type iMemberVar struct {
name string
}
func (p *iMemberVar) Exec(stk *Stack, ctx *Context) {
v, ok := stk.Pop()
if !ok {
panic(ErrRefWithoutObject)
}
stk.Push(&qlang.DataIndex{Data: v, Index: p.name})
}
// MemberVar returns a MemberVar instruction.
//
func MemberVar(name string) Instr {
return &iMemberVar{name}
}
// -----------------------------------------------------------------------------