1 ## our_shell: ysh
2 ## oils_failures_allowed: 0
3
4 #### Object() creates prototype chain
5
6 func Rect_area(this) {
7 return (this.x * this.y)
8 }
9
10 var Rect = Object(null, {area: Rect_area})
11
12 var rect1 = Object(Rect, {x: 3, y: 4})
13 var rect2 = Object(Rect, {x: 10, y: 20})
14
15 # This could change to show the object?
16 # pp test_ (rect)
17
18 # TODO: This should be a bound function
19 #pp asdl_ (rect)
20 #pp (rect.area)
21 #pp (rect->area)
22
23 var area1 = rect1.area()
24 var area2 = rect2.area()
25
26 pp test_ ([rect1.x, rect1.y])
27 echo "area1 = $area1"
28
29 pp test_ ([rect2.x, rect2.y])
30 echo "area2 = $area2"
31
32 #pp test_ (rect1.nonexistent)
33
34 ## STDOUT:
35 (List) [3,4]
36 area1 = 12
37 (List) [10,20]
38 area2 = 200
39 ## END
40
41 #### prototype()
42
43 func Rect_area(this) {
44 return (this.x * this.y)
45 }
46
47 var Rect = Object(null, {area: Rect_area})
48
49 var obj = Object(Rect, {x: 3, y: 4})
50
51 pp test_ (prototype(Rect))
52 pp test_ (prototype(obj))
53
54 ## STDOUT:
55 (Null) null
56 (Obj) ("area":<Func>)
57 ## END
58
59 #### propView()
60
61 var obj = Object(null, {x: 3, y: 4})
62 var props = propView(obj)
63
64 pp test_ (props)
65
66 # object can be mutated
67 setvar props.x = 99
68
69 pp test_ (props)
70
71 var e = propView(null) # error
72
73 ## status: 3
74 ## STDOUT:
75 (Dict) {"x":3,"y":4}
76 (Dict) {"x":99,"y":4}
77 ## END
78
79 #### Mutating method lookup with ->
80
81 func inc(self, n) {
82 setvar self.i += n
83 }
84 var Counter_methods = Object(null, {'M/inc': inc})
85
86 var c = Object(Counter_methods, {i: 5})
87
88 echo $[c.i]
89 call c->inc(3)
90 echo $[c.i]
91
92 ## STDOUT:
93 5
94 8
95 ## END
96
97 #### Mutating method must be up the prototype chain, not on the object
98
99 func inc(self, n) {
100 setvar self.i += n
101 }
102 var c = Object(null, {'M/inc': inc, i: 0})
103
104 call c->inc(3)
105
106 ## status: 3
107 ## STDOUT:
108 ## END
109
110
111 #### Copy to Dict with dict(), and mutate
112
113 var rect = Object(null, {x: 3, y: 4})
114 var d = dict(rect)
115
116 pp test_ (rect)
117 pp test_ (d)
118
119 # Right now, object attributes aren't mutable! Could change this.
120 #
121 setvar rect.x = 99
122 setvar d.x = 100
123
124 pp test_ (rect)
125 pp test_ (d)
126 ## STDOUT:
127 (Obj) ("x":3,"y":4)
128 (Dict) {"x":3,"y":4}
129 (Obj) ("x":99,"y":4)
130 (Dict) {"x":100,"y":4}
131 ## END
132
133 #### setvar obj.attr = and += and ...
134
135 var rect = Object(null, {x: 3, y: 4})
136 pp test_ (rect)
137
138 setvar rect.y = 99
139 pp test_ (rect)
140
141 setvar rect.y += 3
142 pp test_ (rect)
143
144 setvar rect.x *= 5
145 pp test_ (rect)
146
147 ## STDOUT:
148 (Obj) ("x":3,"y":4)
149 (Obj) ("x":3,"y":99)
150 (Obj) ("x":3,"y":102)
151 (Obj) ("x":15,"y":102)
152 ## END
153
154 #### can't encode objects as JSON
155
156 var Rect = Object(null, {})
157
158 json write (Rect)
159 echo 'nope'
160
161 ## status: 1
162 ## STDOUT:
163 ## END
164
165 #### Can all builtin methods with s.upper()
166
167 var s = 'foo'
168 var x = s.upper()
169 var y = "--$[x.lower()]"
170
171 pp test_ (x)
172 pp test_ (y)
173
174 ## STDOUT:
175 (Str) "FOO"
176 (Str) "--foo"
177 ## END
178
179 #### invokable Obj must be have prototype containing __invoke__ of value.Proc - type -t
180
181 proc p (w; self) {
182 pp test_ ([w, self])
183 }
184 p a ({x: 5, y: 6})
185 echo
186
187 var methods = Object(null, {__invoke__: p})
188
189 var o1 = Object(methods, {})
190 type -t o1
191 echo
192
193 # errors
194
195 var o2 = Object(null, {})
196 if ! type -t o2 {
197 echo 'no prototype'
198 }
199
200 var o3 = Object(Object(null, {}), {})
201 if ! type -t o3 {
202 echo 'no __invoke__ method in prototype'
203 }
204
205 var bad_methods = Object(null, {__invoke__: 42})
206 var o4 = Object(bad_methods, {})
207 if ! type -t o4 {
208 echo '__invoke__ of wrong type'
209 }
210
211 ## STDOUT:
212 (List) ["a",{"x":5,"y":6}]
213
214 invokable
215
216 no prototype
217 no __invoke__ method in prototype
218 __invoke__ of wrong type
219 ## END
220
221 #### Object with longer prototype chain
222
223 # prototypal inheritance pattern
224 var superClassMethods = Object(null, {foo: 'zz'})
225 var methods = Object(superClassMethods, {foo: 42, bar: [1,2]})
226 var instance = Object(methods, {foo: 1, bar: 2, x: 3})
227
228 pp test_ (instance)
229
230 ## STDOUT:
231 (Obj) ("foo":1,"bar":2,"x":3) --> ("foo":42,"bar":[1,2]) --> ("foo":"zz")
232 ## END
233
234
235 #### Closures in a loop idiom
236
237 var procs = []
238 for i in (0 .. 3) {
239 proc __invoke__ (; self) {
240 echo "i = $[self.i]"
241 }
242 var methods = Object(null, {__invoke__})
243 var obj = Object(methods, {i})
244 call procs->append(obj)
245 }
246
247 for p in (procs) {
248 p
249 }
250
251 # TODO: sugar
252 # proc p (; self) capture {i} {
253 # echo "i = $[self.i]"
254 # }
255 # call procs->append(p)
256
257 ## STDOUT:
258 i = 0
259 i = 1
260 i = 2
261 ## END