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
|
#include "eval.h"
#include "builtin.h"
#include "exc.h"
#include "consts.h"
#include <cstdio>
extern Pair *empty_list;
FrameObj *eval_stack[EVAL_STACK_SIZE];
void Evaluator::add_builtin_routines() {
#define ADD_ENTRY(name, rout) \
envt->add_binding(new SymObj(name), rout)
#define ADD_BUILTIN_PROC(name, rout) \
ADD_ENTRY(name, new BuiltinProcObj(rout, name))
ADD_ENTRY("if", new SpecialOptIf());
ADD_ENTRY("lambda", new SpecialOptLambda());
ADD_ENTRY("define", new SpecialOptDefine());
ADD_ENTRY("set!", new SpecialOptSet());
ADD_ENTRY("quote", new SpecialOptQuote());
ADD_ENTRY("eval", new SpecialOptEval());
ADD_ENTRY("and", new SpecialOptAnd());
ADD_ENTRY("or", new SpecialOptOr());
ADD_ENTRY("apply", new SpecialOptApply());
ADD_ENTRY("delay", new SpecialOptDelay());
ADD_ENTRY("force", new SpecialOptForce());
ADD_BUILTIN_PROC("+", num_add);
ADD_BUILTIN_PROC("-", num_sub);
ADD_BUILTIN_PROC("*", num_mul);
ADD_BUILTIN_PROC("/", num_div);
ADD_BUILTIN_PROC("<", num_lt);
ADD_BUILTIN_PROC("<=", num_le);
ADD_BUILTIN_PROC(">", num_gt);
ADD_BUILTIN_PROC(">=", num_ge);
ADD_BUILTIN_PROC("=", num_eq);
ADD_BUILTIN_PROC("exact?", num_is_exact);
ADD_BUILTIN_PROC("inexact?", num_is_inexact);
ADD_BUILTIN_PROC("number?", is_number);
ADD_BUILTIN_PROC("complex?", is_complex);
ADD_BUILTIN_PROC("real?", is_real);
ADD_BUILTIN_PROC("rational?", is_rational);
ADD_BUILTIN_PROC("integer?", is_integer);
ADD_BUILTIN_PROC("abs", num_abs);
ADD_BUILTIN_PROC("modulo", num_mod);
ADD_BUILTIN_PROC("remainder", num_rem);
ADD_BUILTIN_PROC("quotient", num_quo);
ADD_BUILTIN_PROC("gcd", num_gcd);
ADD_BUILTIN_PROC("lcm", num_lcm);
ADD_BUILTIN_PROC("not", bool_not);
ADD_BUILTIN_PROC("boolean?", is_boolean);
ADD_BUILTIN_PROC("pair?", is_pair);
ADD_BUILTIN_PROC("cons", make_pair);
ADD_BUILTIN_PROC("car", pair_car);
ADD_BUILTIN_PROC("cdr", pair_cdr);
ADD_BUILTIN_PROC("set-car!", pair_set_car);
ADD_BUILTIN_PROC("set-cdr!", pair_set_cdr);
ADD_BUILTIN_PROC("null?", is_null);
ADD_BUILTIN_PROC("list?", is_list);
ADD_BUILTIN_PROC("list", make_list);
ADD_BUILTIN_PROC("length", length);
ADD_BUILTIN_PROC("append", append);
ADD_BUILTIN_PROC("reverse", reverse);
ADD_BUILTIN_PROC("list-tail", list_tail);
ADD_BUILTIN_PROC("eqv?", is_eqv);
ADD_BUILTIN_PROC("eq?", is_eqv);
ADD_BUILTIN_PROC("equal?", is_equal);
ADD_BUILTIN_PROC("display", display);
ADD_BUILTIN_PROC("string?", is_string);
ADD_BUILTIN_PROC("symbol?", is_symbol);
ADD_BUILTIN_PROC("string<?", string_lt);
ADD_BUILTIN_PROC("string<=?", string_le);
ADD_BUILTIN_PROC("string>?", string_gt);
ADD_BUILTIN_PROC("string<=?", string_ge);
ADD_BUILTIN_PROC("string=?", string_eq);
}
Evaluator::Evaluator() {
envt = new Environment(NULL); // Top-level Environment
add_builtin_routines();
}
void push(Pair * &pc, FrameObj ** &top_ptr, Environment *envt) {
if (pc->car->is_simple_obj()) // Not an opt invocation
{
*top_ptr = envt->get_obj(pc->car); // Objectify the symbol
top_ptr++;
pc = pc->next; // Move to the next instruction
}
else // Operational Invocation
{
if (pc->car == empty_list)
throw NormalError(SYN_ERR_EMPTY_COMB);
*top_ptr++ = new RetAddr(pc); // Push the return address
if (!make_exec(TO_PAIR(pc->car)))
throw TokenError(pc->car->ext_repr(), RUN_ERR_WRONG_NUM_OF_ARGS);
// static_cast because of is_simple_obj() is false
pc = static_cast<Pair*>(pc->car); // Go deeper to enter the call
envt->get_obj(pc->car)->prepare(pc);
}
}
EvalObj *Evaluator::run_expr(Pair *prog) {
FrameObj **top_ptr = eval_stack;
Pair *pc = prog;
Continuation *cont = NULL;
// envt is this->envt
push(pc, top_ptr, envt);
while((*eval_stack)->is_ret_addr())
{
if (top_ptr == eval_stack + EVAL_STACK_SIZE)
throw TokenError("Evaluation", RUN_ERR_STACK_OVERFLOW);
if (pc)
push(pc, top_ptr, envt);
else
{
Pair *args = empty_list;
while (!(*(--top_ptr))->is_ret_addr())
args = new Pair(static_cast<EvalObj*>(*top_ptr), args);
//< static_cast because the while condition
RetAddr *ret_addr = static_cast<RetAddr*>(*top_ptr);
if (!ret_addr->addr)
{
Pair *nexp = TO_PAIR(cont->proc_body->cdr);
cont->proc_body = nexp;
if (nexp == empty_list)
{
*top_ptr = args->car;
envt = cont->envt;
pc = cont->pc->next;
cont = cont->prev_cont;
}
else pc = nexp;
top_ptr++;
}
else
{
EvalObj *opt = args->car;
if (opt->is_opt_obj())
pc = static_cast<OptObj*>(opt)->
call(args, envt, cont, top_ptr);
else
throw TokenError(opt->ext_repr(), SYN_ERR_CAN_NOT_APPLY);
}
}
}
// static_cast because the previous while condition
return static_cast<EvalObj*>(*(eval_stack));
}
|