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
|
#include "gc.h"
#include "objects.h"
//
// Constructors.
//
Object *
make_fixnum(ssize_t num) {
Object *obj = alloc_object(OBJ_TYPE_FIXNUM);
obj->fixnum = num;
return obj;
}
Object *
make_procedure(Object *(*proc)(struct Environment *, struct Object *args)) {
Object *obj = alloc_object(OBJ_TYPE_PROCEDURE);
obj->proc = proc;
return obj;
}
Object *
make_pair(Object *car, Object *cdr) {
Object *obj = alloc_object(OBJ_TYPE_PAIR);
obj->car = car;
obj->cdr = cdr;
return obj;
}
Object *
make_symbol(StringView sv) {
Object *obj = alloc_object(OBJ_TYPE_SYMBOL);
obj->symbol = malloc(sizeof(char) * sv.n);
memcpy(obj->symbol, sv.start, sv.n);
obj->symbol_n = sv.n;
return obj;
}
Object *
make_string(void) {
Object *obj = alloc_object(OBJ_TYPE_STRING);
obj->string = NULL;
obj->string_n = 0;
return obj;
}
void
append_string(Object *obj, const StringView sv) {
assert(obj != NULL);
assert(obj->type == OBJ_TYPE_STRING);
if (sv.n == 0) {
return;
}
obj->string = realloc(obj->string, (obj->string_n + sv.n) * sizeof(char));
memcpy(obj->string + obj->string_n, sv.start, sv.n);
obj->string_n += sv.n;
}
void
display_pair(Object *root) {
display(root->car);
if (root->cdr->type == OBJ_TYPE_PAIR) {
printf(" ");
display_pair(root->cdr);
} else if (root->cdr == obj_nil) {
return;
} else {
printf(" . ");
display(root->cdr);
}
}
void
display(Object *root) {
switch (root->type) {
case OBJ_TYPE_FIXNUM: {
printf("%zd", root->fixnum);
} break;
case OBJ_TYPE_BOOL: {
if (root == obj_true) {
printf("true");
} else {
printf("false");
}
} break;
case OBJ_TYPE_NIL: {
printf("()");
} break;
case OBJ_TYPE_STRING: {
printf("\"%.*s\"", (int)root->string_n, root->string);
} break;
case OBJ_TYPE_SYMBOL: {
printf(":%.*s", (int)root->symbol_n, root->symbol);
} break;
case OBJ_TYPE_PAIR: {
printf("(");
display_pair(root);
printf(")");
} break;
case OBJ_TYPE_LAMBDA:
case OBJ_TYPE_PROCEDURE: {
printf("#{procedure}");
} break;
case OBJ_TYPE_ERR: {
printf("#{error}");
} break;
}
return;
}
bool
obj_eq(Object *a, Object* b) {
if (a->type != b->type) {
return false;
}
switch (a->type) {
case OBJ_TYPE_FIXNUM: {
return a->fixnum == b->fixnum;
} break;
case OBJ_TYPE_STRING: {
if (a->string_n != b->string_n) {
return false;
}
for (size_t i = 0; i < a->string_n; i++) {
if (a->string[i] != b->string[i]) {
return false;
}
}
} break;
case OBJ_TYPE_SYMBOL: {
if (a->symbol_n != b->symbol_n) {
return false;
}
for (size_t i = 0; i < a->symbol_n; i++) {
if (a->symbol[i] != b->symbol[i]) {
return false;
}
}
} break;
default: {
return a == b;
} break;
}
return true;
}
|
