1Obj(3)                           OCaml library                          Obj(3)
2
3
4

NAME

6       Obj - Operations on internal representations of values.
7

Module

9       Module   Obj
10

Documentation

12       Module Obj
13        : sig end
14
15
16       Operations on internal representations of values.
17
18       Not for the casual user.
19
20
21
22
23
24       type t
25
26
27
28
29
30       val repr : 'a -> t
31
32
33
34
35       val obj : t -> 'a
36
37
38
39
40       val magic : 'a -> 'b
41
42
43
44
45       val is_block : t -> bool
46
47
48
49
50       val is_int : t -> bool
51
52
53
54
55       val tag : t -> int
56
57
58
59
60       val size : t -> int
61
62
63
64
65       val reachable_words : t -> int
66
67       Computes  the  total size (in words, including the headers) of all heap
68       blocks accessible from the argument.  Statically allocated  blocks  are
69       excluded.
70
71       @Since 4.04
72
73
74
75       val field : t -> int -> t
76
77
78
79
80       val set_field : t -> int -> t -> unit
81
82       When using flambda:
83
84
85       set_field MUST NOT be called on immutable blocks.  (Blocks allocated in
86       C stubs, or with new_block below, are always considered mutable.)
87
88       The same goes for set_double_field and set_tag .  However, for  set_tag
89       , in the case of immutable blocks where the middle-end optimizers never
90       see code that discriminates on their tag  (for  example  records),  the
91       operation should be safe.  Such uses are nonetheless discouraged.
92
93       For  experts  only:  set_field et al can be made safe by first wrapping
94       the block in Sys.opaque_identity , so any information  about  its  con‐
95       tents will not be propagated.
96
97
98
99       val set_tag : t -> int -> unit
100
101
102
103
104       val double_field : t -> int -> float
105
106
107
108
109       val set_double_field : t -> int -> float -> unit
110
111
112
113
114       val new_block : int -> int -> t
115
116
117
118
119       val dup : t -> t
120
121
122
123
124       val truncate : t -> int -> unit
125
126
127
128
129       val add_offset : t -> Int32.t -> t
130
131
132
133
134       val first_non_constant_constructor_tag : int
135
136
137
138
139       val last_non_constant_constructor_tag : int
140
141
142
143
144       val lazy_tag : int
145
146
147
148
149       val closure_tag : int
150
151
152
153
154       val object_tag : int
155
156
157
158
159       val infix_tag : int
160
161
162
163
164       val forward_tag : int
165
166
167
168
169       val no_scan_tag : int
170
171
172
173
174       val abstract_tag : int
175
176
177
178
179       val string_tag : int
180
181
182
183
184       val double_tag : int
185
186
187
188
189       val double_array_tag : int
190
191
192
193
194       val custom_tag : int
195
196
197
198
199       val final_tag : int
200
201
202
203
204       val int_tag : int
205
206
207
208
209       val out_of_heap_tag : int
210
211
212
213
214       val unaligned_tag : int
215
216
217
218
219       val extension_constructor : 'a -> extension_constructor
220
221
222
223
224       val extension_name : extension_constructor -> string
225
226
227
228
229       val extension_id : extension_constructor -> int
230
231
232
233
234
235       ===  The  following  two  functions  are deprecated. Use module Marshal
236       instead. ===
237
238
239       val marshal : t -> bytes
240
241
242
243
244       val unmarshal : bytes -> int -> t * int
245
246
247
248       module Ephemeron : sig end
249
250
251
252
253
254
255
256OCamldoc                          2019-02-02                            Obj(3)
Impressum