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
|
// Logic for parsing statements
#include <gc.h>
#include <stdbool.h>
#include <string.h>
#include "../ast.h"
#include "../stdlib/util.h"
#include "context.h"
#include "errors.h"
#include "files.h"
#include "parse.h"
#include "statements.h"
#include "suffixes.h"
#include "types.h"
#include "utils.h"
public
ast_t *parse_declaration(parse_ctx_t *ctx, const char *pos) {
const char *start = pos;
ast_t *var = parse_var(ctx, pos);
if (!var) return NULL;
pos = var->end;
spaces(&pos);
if (!match(&pos, ":")) return NULL;
spaces(&pos);
type_ast_t *type = optional(ctx, &pos, parse_type);
spaces(&pos);
ast_t *val = NULL;
if (match(&pos, "=")) {
val = optional(ctx, &pos, parse_extended_expr);
if (!val) {
if (optional(ctx, &pos, parse_use))
parser_err(ctx, start, pos, "'use' statements are only allowed at the top level of a file");
else parser_err(ctx, pos, eol(pos), "This is not a valid expression");
}
}
return NewAST(ctx->file, start, pos, Declare, .var = var, .type = type, .value = val);
}
public
ast_t *parse_assignment(parse_ctx_t *ctx, const char *pos) {
const char *start = pos;
ast_list_t *targets = NULL;
for (;;) {
ast_t *lhs = optional(ctx, &pos, parse_term);
if (!lhs) break;
targets = new (ast_list_t, .ast = lhs, .next = targets);
spaces(&pos);
if (!match(&pos, ",")) break;
whitespace(&pos);
}
if (!targets) return NULL;
spaces(&pos);
if (!match(&pos, "=")) return NULL;
if (match(&pos, "=")) return NULL; // == comparison
ast_list_t *values = NULL;
for (;;) {
ast_t *rhs = optional(ctx, &pos, parse_extended_expr);
if (!rhs) break;
values = new (ast_list_t, .ast = rhs, .next = values);
spaces(&pos);
if (!match(&pos, ",")) break;
whitespace(&pos);
}
REVERSE_LIST(targets);
REVERSE_LIST(values);
return NewAST(ctx->file, start, pos, Assign, .targets = targets, .values = values);
}
public
ast_t *parse_update(parse_ctx_t *ctx, const char *pos) {
const char *start = pos;
ast_t *lhs = optional(ctx, &pos, parse_expr);
if (!lhs) return NULL;
spaces(&pos);
ast_e op;
if (match(&pos, "+=")) op = PlusUpdate;
else if (match(&pos, "++=")) op = ConcatUpdate;
else if (match(&pos, "-=")) op = MinusUpdate;
else if (match(&pos, "*=")) op = MultiplyUpdate;
else if (match(&pos, "/=")) op = DivideUpdate;
else if (match(&pos, "^=")) op = PowerUpdate;
else if (match(&pos, "<<=")) op = LeftShiftUpdate;
else if (match(&pos, "<<<=")) op = UnsignedLeftShiftUpdate;
else if (match(&pos, ">>=")) op = RightShiftUpdate;
else if (match(&pos, ">>>=")) op = UnsignedRightShiftUpdate;
else if (match(&pos, "and=")) op = AndUpdate;
else if (match(&pos, "or=")) op = OrUpdate;
else if (match(&pos, "xor=")) op = XorUpdate;
else return NULL;
ast_t *rhs = expect(ctx, start, &pos, parse_extended_expr, "I expected an expression here");
return new (ast_t, .file = ctx->file, .start = start, .end = pos, .tag = op, .__data.PlusUpdate.lhs = lhs,
.__data.PlusUpdate.rhs = rhs);
}
public
ast_t *parse_doctest(parse_ctx_t *ctx, const char *pos) {
const char *start = pos;
if (!match(&pos, ">>")) return NULL;
spaces(&pos);
ast_t *expr = expect(ctx, start, &pos, parse_statement, "I couldn't parse the expression for this doctest");
whitespace(&pos);
ast_t *expected = NULL;
if (match(&pos, "=")) {
spaces(&pos);
expected = expect(ctx, start, &pos, parse_extended_expr, "I couldn't parse the expected expression here");
} else {
pos = expr->end;
}
return NewAST(ctx->file, start, pos, DocTest, .expr = expr, .expected = expected);
}
public
ast_t *parse_assert(parse_ctx_t *ctx, const char *pos) {
const char *start = pos;
if (!match_word(&pos, "assert")) return NULL;
spaces(&pos);
ast_t *expr = expect(ctx, start, &pos, parse_extended_expr, "I couldn't parse the expression for this assert");
spaces(&pos);
ast_t *message = NULL;
if (match(&pos, ",")) {
whitespace(&pos);
message = expect(ctx, start, &pos, parse_extended_expr, "I couldn't parse the error message for this assert");
} else {
pos = expr->end;
}
return NewAST(ctx->file, start, pos, Assert, .expr = expr, .message = message);
}
public
ast_t *parse_statement(parse_ctx_t *ctx, const char *pos) {
ast_t *stmt = NULL;
if ((stmt = parse_declaration(ctx, pos)) || (stmt = parse_doctest(ctx, pos)) || (stmt = parse_assert(ctx, pos)))
return stmt;
if (!(false || (stmt = parse_update(ctx, pos)) || (stmt = parse_assignment(ctx, pos))))
stmt = parse_extended_expr(ctx, pos);
for (bool progress = (stmt != NULL); progress;) {
ast_t *new_stmt;
progress = false;
if (stmt->tag == Var) {
progress = (false || (new_stmt = parse_method_call_suffix(ctx, stmt))
|| (new_stmt = parse_fncall_suffix(ctx, stmt)));
} else if (stmt->tag == FunctionCall) {
new_stmt = parse_optional_conditional_suffix(ctx, stmt);
progress = (new_stmt != stmt);
}
if (progress) stmt = new_stmt;
}
return stmt;
}
|
