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author | Li Jin <dragon-fly@qq.com> | 2021-04-21 09:36:25 +0800 |
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committer | Li Jin <dragon-fly@qq.com> | 2021-04-21 09:36:25 +0800 |
commit | b7bdf7d5d36825a1a750a74641f6d374dec5d67a (patch) | |
tree | 6b27eb6590e07c07f378305c51d0f5e0779faa83 /src/lua/llex.c | |
parent | b86e5af605a170a3559df0165eac3cb6b665dc49 (diff) | |
download | yuescript-b7bdf7d5d36825a1a750a74641f6d374dec5d67a.tar.gz yuescript-b7bdf7d5d36825a1a750a74641f6d374dec5d67a.tar.bz2 yuescript-b7bdf7d5d36825a1a750a74641f6d374dec5d67a.zip |
adjust some folder levels.
Diffstat (limited to 'src/lua/llex.c')
-rw-r--r-- | src/lua/llex.c | 581 |
1 files changed, 0 insertions, 581 deletions
diff --git a/src/lua/llex.c b/src/lua/llex.c deleted file mode 100644 index e991517..0000000 --- a/src/lua/llex.c +++ /dev/null | |||
@@ -1,581 +0,0 @@ | |||
1 | /* | ||
2 | ** $Id: llex.c $ | ||
3 | ** Lexical Analyzer | ||
4 | ** See Copyright Notice in lua.h | ||
5 | */ | ||
6 | |||
7 | #define llex_c | ||
8 | #define LUA_CORE | ||
9 | |||
10 | #include "lprefix.h" | ||
11 | |||
12 | |||
13 | #include <locale.h> | ||
14 | #include <string.h> | ||
15 | |||
16 | #include "lua.h" | ||
17 | |||
18 | #include "lctype.h" | ||
19 | #include "ldebug.h" | ||
20 | #include "ldo.h" | ||
21 | #include "lgc.h" | ||
22 | #include "llex.h" | ||
23 | #include "lobject.h" | ||
24 | #include "lparser.h" | ||
25 | #include "lstate.h" | ||
26 | #include "lstring.h" | ||
27 | #include "ltable.h" | ||
28 | #include "lzio.h" | ||
29 | |||
30 | |||
31 | |||
32 | #define next(ls) (ls->current = zgetc(ls->z)) | ||
33 | |||
34 | |||
35 | |||
36 | #define currIsNewline(ls) (ls->current == '\n' || ls->current == '\r') | ||
37 | |||
38 | |||
39 | /* ORDER RESERVED */ | ||
40 | static const char *const luaX_tokens [] = { | ||
41 | "and", "break", "do", "else", "elseif", | ||
42 | "end", "false", "for", "function", "goto", "if", | ||
43 | "in", "local", "nil", "not", "or", "repeat", | ||
44 | "return", "then", "true", "until", "while", | ||
45 | "//", "..", "...", "==", ">=", "<=", "~=", | ||
46 | "<<", ">>", "::", "<eof>", | ||
47 | "<number>", "<integer>", "<name>", "<string>" | ||
48 | }; | ||
49 | |||
50 | |||
51 | #define save_and_next(ls) (save(ls, ls->current), next(ls)) | ||
52 | |||
53 | |||
54 | static l_noret lexerror (LexState *ls, const char *msg, int token); | ||
55 | |||
56 | |||
57 | static void save (LexState *ls, int c) { | ||
58 | Mbuffer *b = ls->buff; | ||
59 | if (luaZ_bufflen(b) + 1 > luaZ_sizebuffer(b)) { | ||
60 | size_t newsize; | ||
61 | if (luaZ_sizebuffer(b) >= MAX_SIZE/2) | ||
62 | lexerror(ls, "lexical element too long", 0); | ||
63 | newsize = luaZ_sizebuffer(b) * 2; | ||
64 | luaZ_resizebuffer(ls->L, b, newsize); | ||
65 | } | ||
66 | b->buffer[luaZ_bufflen(b)++] = cast_char(c); | ||
67 | } | ||
68 | |||
69 | |||
70 | void luaX_init (lua_State *L) { | ||
71 | int i; | ||
72 | TString *e = luaS_newliteral(L, LUA_ENV); /* create env name */ | ||
73 | luaC_fix(L, obj2gco(e)); /* never collect this name */ | ||
74 | for (i=0; i<NUM_RESERVED; i++) { | ||
75 | TString *ts = luaS_new(L, luaX_tokens[i]); | ||
76 | luaC_fix(L, obj2gco(ts)); /* reserved words are never collected */ | ||
77 | ts->extra = cast_byte(i+1); /* reserved word */ | ||
78 | } | ||
79 | } | ||
80 | |||
81 | |||
82 | const char *luaX_token2str (LexState *ls, int token) { | ||
83 | if (token < FIRST_RESERVED) { /* single-byte symbols? */ | ||
84 | if (lisprint(token)) | ||
85 | return luaO_pushfstring(ls->L, "'%c'", token); | ||
86 | else /* control character */ | ||
87 | return luaO_pushfstring(ls->L, "'<\\%d>'", token); | ||
88 | } | ||
89 | else { | ||
90 | const char *s = luaX_tokens[token - FIRST_RESERVED]; | ||
91 | if (token < TK_EOS) /* fixed format (symbols and reserved words)? */ | ||
92 | return luaO_pushfstring(ls->L, "'%s'", s); | ||
93 | else /* names, strings, and numerals */ | ||
94 | return s; | ||
95 | } | ||
96 | } | ||
97 | |||
98 | |||
99 | static const char *txtToken (LexState *ls, int token) { | ||
100 | switch (token) { | ||
101 | case TK_NAME: case TK_STRING: | ||
102 | case TK_FLT: case TK_INT: | ||
103 | save(ls, '\0'); | ||
104 | return luaO_pushfstring(ls->L, "'%s'", luaZ_buffer(ls->buff)); | ||
105 | default: | ||
106 | return luaX_token2str(ls, token); | ||
107 | } | ||
108 | } | ||
109 | |||
110 | |||
111 | static l_noret lexerror (LexState *ls, const char *msg, int token) { | ||
112 | msg = luaG_addinfo(ls->L, msg, ls->source, ls->linenumber); | ||
113 | if (token) | ||
114 | luaO_pushfstring(ls->L, "%s near %s", msg, txtToken(ls, token)); | ||
115 | luaD_throw(ls->L, LUA_ERRSYNTAX); | ||
116 | } | ||
117 | |||
118 | |||
119 | l_noret luaX_syntaxerror (LexState *ls, const char *msg) { | ||
120 | lexerror(ls, msg, ls->t.token); | ||
121 | } | ||
122 | |||
123 | |||
124 | /* | ||
125 | ** Creates a new string and anchors it in scanner's table so that it | ||
126 | ** will not be collected until the end of the compilation; by that time | ||
127 | ** it should be anchored somewhere. It also internalizes long strings, | ||
128 | ** ensuring there is only one copy of each unique string. The table | ||
129 | ** here is used as a set: the string enters as the key, while its value | ||
130 | ** is irrelevant. We use the string itself as the value only because it | ||
131 | ** is a TValue readly available. Later, the code generation can change | ||
132 | ** this value. | ||
133 | */ | ||
134 | TString *luaX_newstring (LexState *ls, const char *str, size_t l) { | ||
135 | lua_State *L = ls->L; | ||
136 | TString *ts = luaS_newlstr(L, str, l); /* create new string */ | ||
137 | const TValue *o = luaH_getstr(ls->h, ts); | ||
138 | if (!ttisnil(o)) /* string already present? */ | ||
139 | ts = keystrval(nodefromval(o)); /* get saved copy */ | ||
140 | else { /* not in use yet */ | ||
141 | TValue *stv = s2v(L->top++); /* reserve stack space for string */ | ||
142 | setsvalue(L, stv, ts); /* temporarily anchor the string */ | ||
143 | luaH_finishset(L, ls->h, stv, o, stv); /* t[string] = string */ | ||
144 | /* table is not a metatable, so it does not need to invalidate cache */ | ||
145 | luaC_checkGC(L); | ||
146 | L->top--; /* remove string from stack */ | ||
147 | } | ||
148 | return ts; | ||
149 | } | ||
150 | |||
151 | |||
152 | /* | ||
153 | ** increment line number and skips newline sequence (any of | ||
154 | ** \n, \r, \n\r, or \r\n) | ||
155 | */ | ||
156 | static void inclinenumber (LexState *ls) { | ||
157 | int old = ls->current; | ||
158 | lua_assert(currIsNewline(ls)); | ||
159 | next(ls); /* skip '\n' or '\r' */ | ||
160 | if (currIsNewline(ls) && ls->current != old) | ||
161 | next(ls); /* skip '\n\r' or '\r\n' */ | ||
162 | if (++ls->linenumber >= MAX_INT) | ||
163 | lexerror(ls, "chunk has too many lines", 0); | ||
164 | } | ||
165 | |||
166 | |||
167 | void luaX_setinput (lua_State *L, LexState *ls, ZIO *z, TString *source, | ||
168 | int firstchar) { | ||
169 | ls->t.token = 0; | ||
170 | ls->L = L; | ||
171 | ls->current = firstchar; | ||
172 | ls->lookahead.token = TK_EOS; /* no look-ahead token */ | ||
173 | ls->z = z; | ||
174 | ls->fs = NULL; | ||
175 | ls->linenumber = 1; | ||
176 | ls->lastline = 1; | ||
177 | ls->source = source; | ||
178 | ls->envn = luaS_newliteral(L, LUA_ENV); /* get env name */ | ||
179 | luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER); /* initialize buffer */ | ||
180 | } | ||
181 | |||
182 | |||
183 | |||
184 | /* | ||
185 | ** ======================================================= | ||
186 | ** LEXICAL ANALYZER | ||
187 | ** ======================================================= | ||
188 | */ | ||
189 | |||
190 | |||
191 | static int check_next1 (LexState *ls, int c) { | ||
192 | if (ls->current == c) { | ||
193 | next(ls); | ||
194 | return 1; | ||
195 | } | ||
196 | else return 0; | ||
197 | } | ||
198 | |||
199 | |||
200 | /* | ||
201 | ** Check whether current char is in set 'set' (with two chars) and | ||
202 | ** saves it | ||
203 | */ | ||
204 | static int check_next2 (LexState *ls, const char *set) { | ||
205 | lua_assert(set[2] == '\0'); | ||
206 | if (ls->current == set[0] || ls->current == set[1]) { | ||
207 | save_and_next(ls); | ||
208 | return 1; | ||
209 | } | ||
210 | else return 0; | ||
211 | } | ||
212 | |||
213 | |||
214 | /* LUA_NUMBER */ | ||
215 | /* | ||
216 | ** This function is quite liberal in what it accepts, as 'luaO_str2num' | ||
217 | ** will reject ill-formed numerals. Roughly, it accepts the following | ||
218 | ** pattern: | ||
219 | ** | ||
220 | ** %d(%x|%.|([Ee][+-]?))* | 0[Xx](%x|%.|([Pp][+-]?))* | ||
221 | ** | ||
222 | ** The only tricky part is to accept [+-] only after a valid exponent | ||
223 | ** mark, to avoid reading '3-4' or '0xe+1' as a single number. | ||
224 | ** | ||
225 | ** The caller might have already read an initial dot. | ||
226 | */ | ||
227 | static int read_numeral (LexState *ls, SemInfo *seminfo) { | ||
228 | TValue obj; | ||
229 | const char *expo = "Ee"; | ||
230 | int first = ls->current; | ||
231 | lua_assert(lisdigit(ls->current)); | ||
232 | save_and_next(ls); | ||
233 | if (first == '0' && check_next2(ls, "xX")) /* hexadecimal? */ | ||
234 | expo = "Pp"; | ||
235 | for (;;) { | ||
236 | if (check_next2(ls, expo)) /* exponent mark? */ | ||
237 | check_next2(ls, "-+"); /* optional exponent sign */ | ||
238 | else if (lisxdigit(ls->current) || ls->current == '.') /* '%x|%.' */ | ||
239 | save_and_next(ls); | ||
240 | else break; | ||
241 | } | ||
242 | if (lislalpha(ls->current)) /* is numeral touching a letter? */ | ||
243 | save_and_next(ls); /* force an error */ | ||
244 | save(ls, '\0'); | ||
245 | if (luaO_str2num(luaZ_buffer(ls->buff), &obj) == 0) /* format error? */ | ||
246 | lexerror(ls, "malformed number", TK_FLT); | ||
247 | if (ttisinteger(&obj)) { | ||
248 | seminfo->i = ivalue(&obj); | ||
249 | return TK_INT; | ||
250 | } | ||
251 | else { | ||
252 | lua_assert(ttisfloat(&obj)); | ||
253 | seminfo->r = fltvalue(&obj); | ||
254 | return TK_FLT; | ||
255 | } | ||
256 | } | ||
257 | |||
258 | |||
259 | /* | ||
260 | ** read a sequence '[=*[' or ']=*]', leaving the last bracket. If | ||
261 | ** sequence is well formed, return its number of '='s + 2; otherwise, | ||
262 | ** return 1 if it is a single bracket (no '='s and no 2nd bracket); | ||
263 | ** otherwise (an unfinished '[==...') return 0. | ||
264 | */ | ||
265 | static size_t skip_sep (LexState *ls) { | ||
266 | size_t count = 0; | ||
267 | int s = ls->current; | ||
268 | lua_assert(s == '[' || s == ']'); | ||
269 | save_and_next(ls); | ||
270 | while (ls->current == '=') { | ||
271 | save_and_next(ls); | ||
272 | count++; | ||
273 | } | ||
274 | return (ls->current == s) ? count + 2 | ||
275 | : (count == 0) ? 1 | ||
276 | : 0; | ||
277 | } | ||
278 | |||
279 | |||
280 | static void read_long_string (LexState *ls, SemInfo *seminfo, size_t sep) { | ||
281 | int line = ls->linenumber; /* initial line (for error message) */ | ||
282 | save_and_next(ls); /* skip 2nd '[' */ | ||
283 | if (currIsNewline(ls)) /* string starts with a newline? */ | ||
284 | inclinenumber(ls); /* skip it */ | ||
285 | for (;;) { | ||
286 | switch (ls->current) { | ||
287 | case EOZ: { /* error */ | ||
288 | const char *what = (seminfo ? "string" : "comment"); | ||
289 | const char *msg = luaO_pushfstring(ls->L, | ||
290 | "unfinished long %s (starting at line %d)", what, line); | ||
291 | lexerror(ls, msg, TK_EOS); | ||
292 | break; /* to avoid warnings */ | ||
293 | } | ||
294 | case ']': { | ||
295 | if (skip_sep(ls) == sep) { | ||
296 | save_and_next(ls); /* skip 2nd ']' */ | ||
297 | goto endloop; | ||
298 | } | ||
299 | break; | ||
300 | } | ||
301 | case '\n': case '\r': { | ||
302 | save(ls, '\n'); | ||
303 | inclinenumber(ls); | ||
304 | if (!seminfo) luaZ_resetbuffer(ls->buff); /* avoid wasting space */ | ||
305 | break; | ||
306 | } | ||
307 | default: { | ||
308 | if (seminfo) save_and_next(ls); | ||
309 | else next(ls); | ||
310 | } | ||
311 | } | ||
312 | } endloop: | ||
313 | if (seminfo) | ||
314 | seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + sep, | ||
315 | luaZ_bufflen(ls->buff) - 2 * sep); | ||
316 | } | ||
317 | |||
318 | |||
319 | static void esccheck (LexState *ls, int c, const char *msg) { | ||
320 | if (!c) { | ||
321 | if (ls->current != EOZ) | ||
322 | save_and_next(ls); /* add current to buffer for error message */ | ||
323 | lexerror(ls, msg, TK_STRING); | ||
324 | } | ||
325 | } | ||
326 | |||
327 | |||
328 | static int gethexa (LexState *ls) { | ||
329 | save_and_next(ls); | ||
330 | esccheck (ls, lisxdigit(ls->current), "hexadecimal digit expected"); | ||
331 | return luaO_hexavalue(ls->current); | ||
332 | } | ||
333 | |||
334 | |||
335 | static int readhexaesc (LexState *ls) { | ||
336 | int r = gethexa(ls); | ||
337 | r = (r << 4) + gethexa(ls); | ||
338 | luaZ_buffremove(ls->buff, 2); /* remove saved chars from buffer */ | ||
339 | return r; | ||
340 | } | ||
341 | |||
342 | |||
343 | static unsigned long readutf8esc (LexState *ls) { | ||
344 | unsigned long r; | ||
345 | int i = 4; /* chars to be removed: '\', 'u', '{', and first digit */ | ||
346 | save_and_next(ls); /* skip 'u' */ | ||
347 | esccheck(ls, ls->current == '{', "missing '{'"); | ||
348 | r = gethexa(ls); /* must have at least one digit */ | ||
349 | while (cast_void(save_and_next(ls)), lisxdigit(ls->current)) { | ||
350 | i++; | ||
351 | esccheck(ls, r <= (0x7FFFFFFFu >> 4), "UTF-8 value too large"); | ||
352 | r = (r << 4) + luaO_hexavalue(ls->current); | ||
353 | } | ||
354 | esccheck(ls, ls->current == '}', "missing '}'"); | ||
355 | next(ls); /* skip '}' */ | ||
356 | luaZ_buffremove(ls->buff, i); /* remove saved chars from buffer */ | ||
357 | return r; | ||
358 | } | ||
359 | |||
360 | |||
361 | static void utf8esc (LexState *ls) { | ||
362 | char buff[UTF8BUFFSZ]; | ||
363 | int n = luaO_utf8esc(buff, readutf8esc(ls)); | ||
364 | for (; n > 0; n--) /* add 'buff' to string */ | ||
365 | save(ls, buff[UTF8BUFFSZ - n]); | ||
366 | } | ||
367 | |||
368 | |||
369 | static int readdecesc (LexState *ls) { | ||
370 | int i; | ||
371 | int r = 0; /* result accumulator */ | ||
372 | for (i = 0; i < 3 && lisdigit(ls->current); i++) { /* read up to 3 digits */ | ||
373 | r = 10*r + ls->current - '0'; | ||
374 | save_and_next(ls); | ||
375 | } | ||
376 | esccheck(ls, r <= UCHAR_MAX, "decimal escape too large"); | ||
377 | luaZ_buffremove(ls->buff, i); /* remove read digits from buffer */ | ||
378 | return r; | ||
379 | } | ||
380 | |||
381 | |||
382 | static void read_string (LexState *ls, int del, SemInfo *seminfo) { | ||
383 | save_and_next(ls); /* keep delimiter (for error messages) */ | ||
384 | while (ls->current != del) { | ||
385 | switch (ls->current) { | ||
386 | case EOZ: | ||
387 | lexerror(ls, "unfinished string", TK_EOS); | ||
388 | break; /* to avoid warnings */ | ||
389 | case '\n': | ||
390 | case '\r': | ||
391 | lexerror(ls, "unfinished string", TK_STRING); | ||
392 | break; /* to avoid warnings */ | ||
393 | case '\\': { /* escape sequences */ | ||
394 | int c; /* final character to be saved */ | ||
395 | save_and_next(ls); /* keep '\\' for error messages */ | ||
396 | switch (ls->current) { | ||
397 | case 'a': c = '\a'; goto read_save; | ||
398 | case 'b': c = '\b'; goto read_save; | ||
399 | case 'f': c = '\f'; goto read_save; | ||
400 | case 'n': c = '\n'; goto read_save; | ||
401 | case 'r': c = '\r'; goto read_save; | ||
402 | case 't': c = '\t'; goto read_save; | ||
403 | case 'v': c = '\v'; goto read_save; | ||
404 | case 'x': c = readhexaesc(ls); goto read_save; | ||
405 | case 'u': utf8esc(ls); goto no_save; | ||
406 | case '\n': case '\r': | ||
407 | inclinenumber(ls); c = '\n'; goto only_save; | ||
408 | case '\\': case '\"': case '\'': | ||
409 | c = ls->current; goto read_save; | ||
410 | case EOZ: goto no_save; /* will raise an error next loop */ | ||
411 | case 'z': { /* zap following span of spaces */ | ||
412 | luaZ_buffremove(ls->buff, 1); /* remove '\\' */ | ||
413 | next(ls); /* skip the 'z' */ | ||
414 | while (lisspace(ls->current)) { | ||
415 | if (currIsNewline(ls)) inclinenumber(ls); | ||
416 | else next(ls); | ||
417 | } | ||
418 | goto no_save; | ||
419 | } | ||
420 | default: { | ||
421 | esccheck(ls, lisdigit(ls->current), "invalid escape sequence"); | ||
422 | c = readdecesc(ls); /* digital escape '\ddd' */ | ||
423 | goto only_save; | ||
424 | } | ||
425 | } | ||
426 | read_save: | ||
427 | next(ls); | ||
428 | /* go through */ | ||
429 | only_save: | ||
430 | luaZ_buffremove(ls->buff, 1); /* remove '\\' */ | ||
431 | save(ls, c); | ||
432 | /* go through */ | ||
433 | no_save: break; | ||
434 | } | ||
435 | default: | ||
436 | save_and_next(ls); | ||
437 | } | ||
438 | } | ||
439 | save_and_next(ls); /* skip delimiter */ | ||
440 | seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + 1, | ||
441 | luaZ_bufflen(ls->buff) - 2); | ||
442 | } | ||
443 | |||
444 | |||
445 | static int llex (LexState *ls, SemInfo *seminfo) { | ||
446 | luaZ_resetbuffer(ls->buff); | ||
447 | for (;;) { | ||
448 | switch (ls->current) { | ||
449 | case '\n': case '\r': { /* line breaks */ | ||
450 | inclinenumber(ls); | ||
451 | break; | ||
452 | } | ||
453 | case ' ': case '\f': case '\t': case '\v': { /* spaces */ | ||
454 | next(ls); | ||
455 | break; | ||
456 | } | ||
457 | case '-': { /* '-' or '--' (comment) */ | ||
458 | next(ls); | ||
459 | if (ls->current != '-') return '-'; | ||
460 | /* else is a comment */ | ||
461 | next(ls); | ||
462 | if (ls->current == '[') { /* long comment? */ | ||
463 | size_t sep = skip_sep(ls); | ||
464 | luaZ_resetbuffer(ls->buff); /* 'skip_sep' may dirty the buffer */ | ||
465 | if (sep >= 2) { | ||
466 | read_long_string(ls, NULL, sep); /* skip long comment */ | ||
467 | luaZ_resetbuffer(ls->buff); /* previous call may dirty the buff. */ | ||
468 | break; | ||
469 | } | ||
470 | } | ||
471 | /* else short comment */ | ||
472 | while (!currIsNewline(ls) && ls->current != EOZ) | ||
473 | next(ls); /* skip until end of line (or end of file) */ | ||
474 | break; | ||
475 | } | ||
476 | case '[': { /* long string or simply '[' */ | ||
477 | size_t sep = skip_sep(ls); | ||
478 | if (sep >= 2) { | ||
479 | read_long_string(ls, seminfo, sep); | ||
480 | return TK_STRING; | ||
481 | } | ||
482 | else if (sep == 0) /* '[=...' missing second bracket? */ | ||
483 | lexerror(ls, "invalid long string delimiter", TK_STRING); | ||
484 | return '['; | ||
485 | } | ||
486 | case '=': { | ||
487 | next(ls); | ||
488 | if (check_next1(ls, '=')) return TK_EQ; /* '==' */ | ||
489 | else return '='; | ||
490 | } | ||
491 | case '<': { | ||
492 | next(ls); | ||
493 | if (check_next1(ls, '=')) return TK_LE; /* '<=' */ | ||
494 | else if (check_next1(ls, '<')) return TK_SHL; /* '<<' */ | ||
495 | else return '<'; | ||
496 | } | ||
497 | case '>': { | ||
498 | next(ls); | ||
499 | if (check_next1(ls, '=')) return TK_GE; /* '>=' */ | ||
500 | else if (check_next1(ls, '>')) return TK_SHR; /* '>>' */ | ||
501 | else return '>'; | ||
502 | } | ||
503 | case '/': { | ||
504 | next(ls); | ||
505 | if (check_next1(ls, '/')) return TK_IDIV; /* '//' */ | ||
506 | else return '/'; | ||
507 | } | ||
508 | case '~': { | ||
509 | next(ls); | ||
510 | if (check_next1(ls, '=')) return TK_NE; /* '~=' */ | ||
511 | else return '~'; | ||
512 | } | ||
513 | case ':': { | ||
514 | next(ls); | ||
515 | if (check_next1(ls, ':')) return TK_DBCOLON; /* '::' */ | ||
516 | else return ':'; | ||
517 | } | ||
518 | case '"': case '\'': { /* short literal strings */ | ||
519 | read_string(ls, ls->current, seminfo); | ||
520 | return TK_STRING; | ||
521 | } | ||
522 | case '.': { /* '.', '..', '...', or number */ | ||
523 | save_and_next(ls); | ||
524 | if (check_next1(ls, '.')) { | ||
525 | if (check_next1(ls, '.')) | ||
526 | return TK_DOTS; /* '...' */ | ||
527 | else return TK_CONCAT; /* '..' */ | ||
528 | } | ||
529 | else if (!lisdigit(ls->current)) return '.'; | ||
530 | else return read_numeral(ls, seminfo); | ||
531 | } | ||
532 | case '0': case '1': case '2': case '3': case '4': | ||
533 | case '5': case '6': case '7': case '8': case '9': { | ||
534 | return read_numeral(ls, seminfo); | ||
535 | } | ||
536 | case EOZ: { | ||
537 | return TK_EOS; | ||
538 | } | ||
539 | default: { | ||
540 | if (lislalpha(ls->current)) { /* identifier or reserved word? */ | ||
541 | TString *ts; | ||
542 | do { | ||
543 | save_and_next(ls); | ||
544 | } while (lislalnum(ls->current)); | ||
545 | ts = luaX_newstring(ls, luaZ_buffer(ls->buff), | ||
546 | luaZ_bufflen(ls->buff)); | ||
547 | seminfo->ts = ts; | ||
548 | if (isreserved(ts)) /* reserved word? */ | ||
549 | return ts->extra - 1 + FIRST_RESERVED; | ||
550 | else { | ||
551 | return TK_NAME; | ||
552 | } | ||
553 | } | ||
554 | else { /* single-char tokens ('+', '*', '%', '{', '}', ...) */ | ||
555 | int c = ls->current; | ||
556 | next(ls); | ||
557 | return c; | ||
558 | } | ||
559 | } | ||
560 | } | ||
561 | } | ||
562 | } | ||
563 | |||
564 | |||
565 | void luaX_next (LexState *ls) { | ||
566 | ls->lastline = ls->linenumber; | ||
567 | if (ls->lookahead.token != TK_EOS) { /* is there a look-ahead token? */ | ||
568 | ls->t = ls->lookahead; /* use this one */ | ||
569 | ls->lookahead.token = TK_EOS; /* and discharge it */ | ||
570 | } | ||
571 | else | ||
572 | ls->t.token = llex(ls, &ls->t.seminfo); /* read next token */ | ||
573 | } | ||
574 | |||
575 | |||
576 | int luaX_lookahead (LexState *ls) { | ||
577 | lua_assert(ls->lookahead.token == TK_EOS); | ||
578 | ls->lookahead.token = llex(ls, &ls->lookahead.seminfo); | ||
579 | return ls->lookahead.token; | ||
580 | } | ||
581 | |||