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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
#include "EXTERN.h"
#include "perl.h"
#include "callparser1.h"
#include "XSUB.h"
#ifndef cv_clone
#define cv_clone(a) Perl_cv_clone(aTHX_ a)
#endif
static SV *parser_fn(OP *(fn)(pTHX_ U32), bool named)
{
I32 floor;
CV *code;
U8 errors;
ENTER;
PL_curcop = &PL_compiling;
SAVEVPTR(PL_op);
SAVEI8(PL_parser->error_count);
PL_parser->error_count = 0;
floor = start_subparse(0, named ? 0 : CVf_ANON);
code = newATTRSUB(floor, NULL, NULL, NULL, fn(aTHX_ 0));
errors = PL_parser->error_count;
LEAVE;
if (errors) {
++PL_parser->error_count;
return newSV(0);
}
else {
if (CvCLONE(code)) {
code = cv_clone(code);
}
return newRV_inc((SV*)code);
}
}
static OP *parser_callback(pTHX_ GV *namegv, SV *psobj, U32 *flagsp)
{
dSP;
SV *args_generator;
SV *statement = NULL;
I32 count;
/* call the parser callback
* it should take no arguments and return a coderef which, when called,
* produces the arguments to the keyword function
* the optree we want to generate is for something like
* mykeyword($code->())
* where $code is the thing returned by the parser function
*/
PUSHMARK(SP);
mXPUSHp(GvNAME(namegv), GvNAMELEN(namegv));
PUTBACK;
count = call_sv(psobj, G_ARRAY);
SPAGAIN;
if (count > 1) {
statement = POPs;
}
args_generator = SvREFCNT_inc(POPs);
PUTBACK;
if (!SvROK(args_generator) || SvTYPE(SvRV(args_generator)) != SVt_PVCV) {
croak("The parser function for %s must return a coderef, not %"SVf,
GvNAME(namegv), args_generator);
}
if (SvTRUE(statement)) {
*flagsp |= CALLPARSER_STATEMENT;
}
return newUNOP(OP_ENTERSUB, OPf_STACKED,
newCVREF(0, newSVOP(OP_CONST, 0, args_generator)));
}
/* TODO:
* - "parse a variable name"
* - "parse a quoted string"
* - "create a new lexical variable" (maybe?)
*/
MODULE = Parse::Keyword PACKAGE = Parse::Keyword
PROTOTYPES: DISABLE
void
install_keyword_handler(keyword, handler)
SV *keyword
SV *handler
CODE:
cv_set_call_parser((CV*)SvRV(keyword), parser_callback, handler);
SV *
lex_peek(len = 1)
UV len
CODE:
PL_curcop = &PL_compiling;
/* XXX before 5.19.2, lex_next_chunk when we aren't at the end of a line
* just breaks things entirely (the parser no longer sees the text that is
* read in). this is (i think inadvertently) fixed in 5.19.2 (21791330a),
* but it still screws up the line numbers of everything that follows. so,
* the workaround is just to not call lex_next_chunk unless we're at the
* end of a line. this is a bit limiting, but should rarely come up in
* practice.
*/
/*
while (PL_parser->bufend - PL_parser->bufptr < len) {
if (!lex_next_chunk(0)) {
break;
}
}
*/
if (PL_parser->bufptr == PL_parser->bufend) {
lex_next_chunk(0);
}
if (PL_parser->bufend - PL_parser->bufptr < len) {
len = PL_parser->bufend - PL_parser->bufptr;
}
RETVAL = newSVpvn(PL_parser->bufptr, len); /* XXX unicode? */
OUTPUT:
RETVAL
void
lex_read(len = 1)
UV len
CODE:
PL_curcop = &PL_compiling;
lex_read_to(PL_parser->bufptr + len);
void
lex_read_space()
CODE:
PL_curcop = &PL_compiling;
lex_read_space(0);
void
lex_stuff(str)
SV *str
CODE:
PL_curcop = &PL_compiling;
lex_stuff_sv(str, 0);
SV *
parse_block(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_block, named);
OUTPUT:
RETVAL
SV *
parse_stmtseq(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_stmtseq, named);
OUTPUT:
RETVAL
SV *
parse_fullstmt(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_fullstmt, named);
OUTPUT:
RETVAL
SV *
parse_barestmt(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_barestmt, named);
OUTPUT:
RETVAL
SV *
parse_fullexpr(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_fullexpr, named);
OUTPUT:
RETVAL
SV *
parse_listexpr(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_listexpr, named);
OUTPUT:
RETVAL
SV *
parse_termexpr(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_termexpr, named);
OUTPUT:
RETVAL
SV *
parse_arithexpr(named = FALSE)
bool named
CODE:
RETVAL = parser_fn(Perl_parse_arithexpr, named);
OUTPUT:
RETVAL
SV *
compiling_package()
CODE:
RETVAL = newSVsv(PL_curstname);
OUTPUT:
RETVAL
|
