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| 1 # ----------------------------------------------------------------------------- |
| 2 # ply: lex.py |
| 3 # |
| 4 # Author: David M. Beazley (dave@dabeaz.com) |
| 5 # |
| 6 # Copyright (C) 2001-2009, David M. Beazley |
| 7 # |
| 8 # This library is free software; you can redistribute it and/or |
| 9 # modify it under the terms of the GNU Lesser General Public |
| 10 # License as published by the Free Software Foundation; either |
| 11 # version 2.1 of the License, or (at your option) any later version. |
| 12 # |
| 13 # This library is distributed in the hope that it will be useful, |
| 14 # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 # Lesser General Public License for more details. |
| 17 # |
| 18 # You should have received a copy of the GNU Lesser General Public |
| 19 # License along with this library; if not, write to the Free Software |
| 20 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 21 # |
| 22 # See the file COPYING for a complete copy of the LGPL. |
| 23 # ----------------------------------------------------------------------------- |
| 24 |
| 25 __version__ = "3.0" |
| 26 __tabversion__ = "3.0" # Version of table file used |
| 27 |
| 28 import re, sys, types, copy, os |
| 29 |
| 30 # This tuple contains known string types |
| 31 try: |
| 32 # Python 2.6 |
| 33 StringTypes = (types.StringType, types.UnicodeType) |
| 34 except AttributeError: |
| 35 # Python 3.0 |
| 36 StringTypes = (str, bytes) |
| 37 |
| 38 # Extract the code attribute of a function. Different implementations |
| 39 # are for Python 2/3 compatibility. |
| 40 |
| 41 if sys.version_info[0] < 3: |
| 42 def func_code(f): |
| 43 return f.func_code |
| 44 else: |
| 45 def func_code(f): |
| 46 return f.__code__ |
| 47 |
| 48 # This regular expression is used to match valid token names |
| 49 _is_identifier = re.compile(r'^[a-zA-Z0-9_]+$') |
| 50 |
| 51 # Exception thrown when invalid token encountered and no default error |
| 52 # handler is defined. |
| 53 |
| 54 class LexError(Exception): |
| 55 def __init__(self,message,s): |
| 56 self.args = (message,) |
| 57 self.text = s |
| 58 |
| 59 # Token class. This class is used to represent the tokens produced. |
| 60 class LexToken(object): |
| 61 def __str__(self): |
| 62 return "LexToken(%s,%r,%d,%d)" % (self.type,self.value,self.lineno,self.
lexpos) |
| 63 def __repr__(self): |
| 64 return str(self) |
| 65 |
| 66 # This object is a stand-in for a logging object created by the |
| 67 # logging module. |
| 68 |
| 69 class PlyLogger(object): |
| 70 def __init__(self,f): |
| 71 self.f = f |
| 72 def critical(self,msg,*args,**kwargs): |
| 73 self.f.write((msg % args) + "\n") |
| 74 |
| 75 def warning(self,msg,*args,**kwargs): |
| 76 self.f.write("WARNING: "+ (msg % args) + "\n") |
| 77 |
| 78 def error(self,msg,*args,**kwargs): |
| 79 self.f.write("ERROR: " + (msg % args) + "\n") |
| 80 |
| 81 info = critical |
| 82 debug = critical |
| 83 |
| 84 # Null logger is used when no output is generated. Does nothing. |
| 85 class NullLogger(object): |
| 86 def __getattribute__(self,name): |
| 87 return self |
| 88 def __call__(self,*args,**kwargs): |
| 89 return self |
| 90 |
| 91 # ----------------------------------------------------------------------------- |
| 92 # === Lexing Engine === |
| 93 # |
| 94 # The following Lexer class implements the lexer runtime. There are only |
| 95 # a few public methods and attributes: |
| 96 # |
| 97 # input() - Store a new string in the lexer |
| 98 # token() - Get the next token |
| 99 # clone() - Clone the lexer |
| 100 # |
| 101 # lineno - Current line number |
| 102 # lexpos - Current position in the input string |
| 103 # ----------------------------------------------------------------------------- |
| 104 |
| 105 class Lexer: |
| 106 def __init__(self): |
| 107 self.lexre = None # Master regular expression. This is a lis
t of |
| 108 # tuples (re,findex) where re is a compile
d |
| 109 # regular expression and findex is a list |
| 110 # mapping regex group numbers to rules |
| 111 self.lexretext = None # Current regular expression strings |
| 112 self.lexstatere = {} # Dictionary mapping lexer states to maste
r regexs |
| 113 self.lexstateretext = {} # Dictionary mapping lexer states to regex
strings |
| 114 self.lexstaterenames = {} # Dictionary mapping lexer states to symbo
l names |
| 115 self.lexstate = "INITIAL" # Current lexer state |
| 116 self.lexstatestack = [] # Stack of lexer states |
| 117 self.lexstateinfo = None # State information |
| 118 self.lexstateignore = {} # Dictionary of ignored characters for eac
h state |
| 119 self.lexstateerrorf = {} # Dictionary of error functions for each s
tate |
| 120 self.lexreflags = 0 # Optional re compile flags |
| 121 self.lexdata = None # Actual input data (as a string) |
| 122 self.lexpos = 0 # Current position in input text |
| 123 self.lexlen = 0 # Length of the input text |
| 124 self.lexerrorf = None # Error rule (if any) |
| 125 self.lextokens = None # List of valid tokens |
| 126 self.lexignore = "" # Ignored characters |
| 127 self.lexliterals = "" # Literal characters that can be passed th
rough |
| 128 self.lexmodule = None # Module |
| 129 self.lineno = 1 # Current line number |
| 130 self.lexoptimize = 0 # Optimized mode |
| 131 |
| 132 def clone(self,object=None): |
| 133 c = copy.copy(self) |
| 134 |
| 135 # If the object parameter has been supplied, it means we are attaching t
he |
| 136 # lexer to a new object. In this case, we have to rebind all methods in |
| 137 # the lexstatere and lexstateerrorf tables. |
| 138 |
| 139 if object: |
| 140 newtab = { } |
| 141 for key, ritem in self.lexstatere.items(): |
| 142 newre = [] |
| 143 for cre, findex in ritem: |
| 144 newfindex = [] |
| 145 for f in findex: |
| 146 if not f or not f[0]: |
| 147 newfindex.append(f) |
| 148 continue |
| 149 newfindex.append((getattr(object,f[0].__name__),f[1])) |
| 150 newre.append((cre,newfindex)) |
| 151 newtab[key] = newre |
| 152 c.lexstatere = newtab |
| 153 c.lexstateerrorf = { } |
| 154 for key, ef in self.lexstateerrorf.items(): |
| 155 c.lexstateerrorf[key] = getattr(object,ef.__name__) |
| 156 c.lexmodule = object |
| 157 return c |
| 158 |
| 159 # ------------------------------------------------------------ |
| 160 # writetab() - Write lexer information to a table file |
| 161 # ------------------------------------------------------------ |
| 162 def writetab(self,tabfile,outputdir=""): |
| 163 if isinstance(tabfile,types.ModuleType): |
| 164 return |
| 165 basetabfilename = tabfile.split(".")[-1] |
| 166 filename = os.path.join(outputdir,basetabfilename)+".py" |
| 167 tf = open(filename,"w") |
| 168 tf.write("# %s.py. This file automatically created by PLY (version %s).
Don't edit!\n" % (tabfile,__version__)) |
| 169 tf.write("_tabversion = %s\n" % repr(__version__)) |
| 170 tf.write("_lextokens = %s\n" % repr(self.lextokens)) |
| 171 tf.write("_lexreflags = %s\n" % repr(self.lexreflags)) |
| 172 tf.write("_lexliterals = %s\n" % repr(self.lexliterals)) |
| 173 tf.write("_lexstateinfo = %s\n" % repr(self.lexstateinfo)) |
| 174 |
| 175 tabre = { } |
| 176 # Collect all functions in the initial state |
| 177 initial = self.lexstatere["INITIAL"] |
| 178 initialfuncs = [] |
| 179 for part in initial: |
| 180 for f in part[1]: |
| 181 if f and f[0]: |
| 182 initialfuncs.append(f) |
| 183 |
| 184 for key, lre in self.lexstatere.items(): |
| 185 titem = [] |
| 186 for i in range(len(lre)): |
| 187 titem.append((self.lexstateretext[key][i],_funcs_to_names(lre[
i][1],self.lexstaterenames[key][i]))) |
| 188 tabre[key] = titem |
| 189 |
| 190 tf.write("_lexstatere = %s\n" % repr(tabre)) |
| 191 tf.write("_lexstateignore = %s\n" % repr(self.lexstateignore)) |
| 192 |
| 193 taberr = { } |
| 194 for key, ef in self.lexstateerrorf.items(): |
| 195 if ef: |
| 196 taberr[key] = ef.__name__ |
| 197 else: |
| 198 taberr[key] = None |
| 199 tf.write("_lexstateerrorf = %s\n" % repr(taberr)) |
| 200 tf.close() |
| 201 |
| 202 # ------------------------------------------------------------ |
| 203 # readtab() - Read lexer information from a tab file |
| 204 # ------------------------------------------------------------ |
| 205 def readtab(self,tabfile,fdict): |
| 206 if isinstance(tabfile,types.ModuleType): |
| 207 lextab = tabfile |
| 208 else: |
| 209 if sys.version_info[0] < 3: |
| 210 exec("import %s as lextab" % tabfile) |
| 211 else: |
| 212 env = { } |
| 213 exec("import %s as lextab" % tabfile, env,env) |
| 214 lextab = env['lextab'] |
| 215 |
| 216 if getattr(lextab,"_tabversion","0.0") != __version__: |
| 217 raise ImportError("Inconsistent PLY version") |
| 218 |
| 219 self.lextokens = lextab._lextokens |
| 220 self.lexreflags = lextab._lexreflags |
| 221 self.lexliterals = lextab._lexliterals |
| 222 self.lexstateinfo = lextab._lexstateinfo |
| 223 self.lexstateignore = lextab._lexstateignore |
| 224 self.lexstatere = { } |
| 225 self.lexstateretext = { } |
| 226 for key,lre in lextab._lexstatere.items(): |
| 227 titem = [] |
| 228 txtitem = [] |
| 229 for i in range(len(lre)): |
| 230 titem.append((re.compile(lre[i][0],lextab._lexreflags),_names_
to_funcs(lre[i][1],fdict))) |
| 231 txtitem.append(lre[i][0]) |
| 232 self.lexstatere[key] = titem |
| 233 self.lexstateretext[key] = txtitem |
| 234 self.lexstateerrorf = { } |
| 235 for key,ef in lextab._lexstateerrorf.items(): |
| 236 self.lexstateerrorf[key] = fdict[ef] |
| 237 self.begin('INITIAL') |
| 238 |
| 239 # ------------------------------------------------------------ |
| 240 # input() - Push a new string into the lexer |
| 241 # ------------------------------------------------------------ |
| 242 def input(self,s): |
| 243 # Pull off the first character to see if s looks like a string |
| 244 c = s[:1] |
| 245 if not isinstance(c,StringTypes): |
| 246 raise ValueError("Expected a string") |
| 247 self.lexdata = s |
| 248 self.lexpos = 0 |
| 249 self.lexlen = len(s) |
| 250 |
| 251 # ------------------------------------------------------------ |
| 252 # begin() - Changes the lexing state |
| 253 # ------------------------------------------------------------ |
| 254 def begin(self,state): |
| 255 if not state in self.lexstatere: |
| 256 raise ValueError("Undefined state") |
| 257 self.lexre = self.lexstatere[state] |
| 258 self.lexretext = self.lexstateretext[state] |
| 259 self.lexignore = self.lexstateignore.get(state,"") |
| 260 self.lexerrorf = self.lexstateerrorf.get(state,None) |
| 261 self.lexstate = state |
| 262 |
| 263 # ------------------------------------------------------------ |
| 264 # push_state() - Changes the lexing state and saves old on stack |
| 265 # ------------------------------------------------------------ |
| 266 def push_state(self,state): |
| 267 self.lexstatestack.append(self.lexstate) |
| 268 self.begin(state) |
| 269 |
| 270 # ------------------------------------------------------------ |
| 271 # pop_state() - Restores the previous state |
| 272 # ------------------------------------------------------------ |
| 273 def pop_state(self): |
| 274 self.begin(self.lexstatestack.pop()) |
| 275 |
| 276 # ------------------------------------------------------------ |
| 277 # current_state() - Returns the current lexing state |
| 278 # ------------------------------------------------------------ |
| 279 def current_state(self): |
| 280 return self.lexstate |
| 281 |
| 282 # ------------------------------------------------------------ |
| 283 # skip() - Skip ahead n characters |
| 284 # ------------------------------------------------------------ |
| 285 def skip(self,n): |
| 286 self.lexpos += n |
| 287 |
| 288 # ------------------------------------------------------------ |
| 289 # opttoken() - Return the next token from the Lexer |
| 290 # |
| 291 # Note: This function has been carefully implemented to be as fast |
| 292 # as possible. Don't make changes unless you really know what |
| 293 # you are doing |
| 294 # ------------------------------------------------------------ |
| 295 def token(self): |
| 296 # Make local copies of frequently referenced attributes |
| 297 lexpos = self.lexpos |
| 298 lexlen = self.lexlen |
| 299 lexignore = self.lexignore |
| 300 lexdata = self.lexdata |
| 301 |
| 302 while lexpos < lexlen: |
| 303 # This code provides some short-circuit code for whitespace, tabs, a
nd other ignored characters |
| 304 if lexdata[lexpos] in lexignore: |
| 305 lexpos += 1 |
| 306 continue |
| 307 |
| 308 # Look for a regular expression match |
| 309 for lexre,lexindexfunc in self.lexre: |
| 310 m = lexre.match(lexdata,lexpos) |
| 311 if not m: continue |
| 312 |
| 313 # Create a token for return |
| 314 tok = LexToken() |
| 315 tok.value = m.group() |
| 316 tok.lineno = self.lineno |
| 317 tok.lexpos = lexpos |
| 318 |
| 319 i = m.lastindex |
| 320 func,tok.type = lexindexfunc[i] |
| 321 |
| 322 if not func: |
| 323 # If no token type was set, it's an ignored token |
| 324 if tok.type: |
| 325 self.lexpos = m.end() |
| 326 return tok |
| 327 else: |
| 328 lexpos = m.end() |
| 329 break |
| 330 |
| 331 lexpos = m.end() |
| 332 |
| 333 # If token is processed by a function, call it |
| 334 |
| 335 tok.lexer = self # Set additional attributes useful in toke
n rules |
| 336 self.lexmatch = m |
| 337 self.lexpos = lexpos |
| 338 |
| 339 newtok = func(tok) |
| 340 |
| 341 # Every function must return a token, if nothing, we just move t
o next token |
| 342 if not newtok: |
| 343 lexpos = self.lexpos # This is here in case user
has updated lexpos. |
| 344 lexignore = self.lexignore # This is here in case there
was a state change |
| 345 break |
| 346 |
| 347 # Verify type of the token. If not in the token map, raise an e
rror |
| 348 if not self.lexoptimize: |
| 349 if not newtok.type in self.lextokens: |
| 350 raise LexError("%s:%d: Rule '%s' returned an unknown tok
en type '%s'" % ( |
| 351 func_code(func).co_filename, func_code(func).co_firs
tlineno, |
| 352 func.__name__, newtok.type),lexdata[lexpos:]) |
| 353 |
| 354 return newtok |
| 355 else: |
| 356 # No match, see if in literals |
| 357 if lexdata[lexpos] in self.lexliterals: |
| 358 tok = LexToken() |
| 359 tok.value = lexdata[lexpos] |
| 360 tok.lineno = self.lineno |
| 361 tok.type = tok.value |
| 362 tok.lexpos = lexpos |
| 363 self.lexpos = lexpos + 1 |
| 364 return tok |
| 365 |
| 366 # No match. Call t_error() if defined. |
| 367 if self.lexerrorf: |
| 368 tok = LexToken() |
| 369 tok.value = self.lexdata[lexpos:] |
| 370 tok.lineno = self.lineno |
| 371 tok.type = "error" |
| 372 tok.lexer = self |
| 373 tok.lexpos = lexpos |
| 374 self.lexpos = lexpos |
| 375 newtok = self.lexerrorf(tok) |
| 376 if lexpos == self.lexpos: |
| 377 # Error method didn't change text position at all. This
is an error. |
| 378 raise LexError("Scanning error. Illegal character '%s'"
% (lexdata[lexpos]), lexdata[lexpos:]) |
| 379 lexpos = self.lexpos |
| 380 if not newtok: continue |
| 381 return newtok |
| 382 |
| 383 self.lexpos = lexpos |
| 384 raise LexError("Illegal character '%s' at index %d" % (lexdata[l
expos],lexpos), lexdata[lexpos:]) |
| 385 |
| 386 self.lexpos = lexpos + 1 |
| 387 if self.lexdata is None: |
| 388 raise RuntimeError("No input string given with input()") |
| 389 return None |
| 390 |
| 391 # Iterator interface |
| 392 def __iter__(self): |
| 393 return self |
| 394 |
| 395 def next(self): |
| 396 t = self.token() |
| 397 if t is None: |
| 398 raise StopIteration |
| 399 return t |
| 400 |
| 401 __next__ = next |
| 402 |
| 403 # ----------------------------------------------------------------------------- |
| 404 # ==== Lex Builder === |
| 405 # |
| 406 # The functions and classes below are used to collect lexing information |
| 407 # and build a Lexer object from it. |
| 408 # ----------------------------------------------------------------------------- |
| 409 |
| 410 # ----------------------------------------------------------------------------- |
| 411 # get_caller_module_dict() |
| 412 # |
| 413 # This function returns a dictionary containing all of the symbols defined withi
n |
| 414 # a caller further down the call stack. This is used to get the environment |
| 415 # associated with the yacc() call if none was provided. |
| 416 # ----------------------------------------------------------------------------- |
| 417 |
| 418 def get_caller_module_dict(levels): |
| 419 try: |
| 420 raise RuntimeError |
| 421 except RuntimeError: |
| 422 e,b,t = sys.exc_info() |
| 423 f = t.tb_frame |
| 424 while levels > 0: |
| 425 f = f.f_back |
| 426 levels -= 1 |
| 427 ldict = f.f_globals.copy() |
| 428 if f.f_globals != f.f_locals: |
| 429 ldict.update(f.f_locals) |
| 430 |
| 431 return ldict |
| 432 |
| 433 # ----------------------------------------------------------------------------- |
| 434 # _funcs_to_names() |
| 435 # |
| 436 # Given a list of regular expression functions, this converts it to a list |
| 437 # suitable for output to a table file |
| 438 # ----------------------------------------------------------------------------- |
| 439 |
| 440 def _funcs_to_names(funclist,namelist): |
| 441 result = [] |
| 442 for f,name in zip(funclist,namelist): |
| 443 if f and f[0]: |
| 444 result.append((name, f[1])) |
| 445 else: |
| 446 result.append(f) |
| 447 return result |
| 448 |
| 449 # ----------------------------------------------------------------------------- |
| 450 # _names_to_funcs() |
| 451 # |
| 452 # Given a list of regular expression function names, this converts it back to |
| 453 # functions. |
| 454 # ----------------------------------------------------------------------------- |
| 455 |
| 456 def _names_to_funcs(namelist,fdict): |
| 457 result = [] |
| 458 for n in namelist: |
| 459 if n and n[0]: |
| 460 result.append((fdict[n[0]],n[1])) |
| 461 else: |
| 462 result.append(n) |
| 463 return result |
| 464 |
| 465 # ----------------------------------------------------------------------------- |
| 466 # _form_master_re() |
| 467 # |
| 468 # This function takes a list of all of the regex components and attempts to |
| 469 # form the master regular expression. Given limitations in the Python re |
| 470 # module, it may be necessary to break the master regex into separate expression
s. |
| 471 # ----------------------------------------------------------------------------- |
| 472 |
| 473 def _form_master_re(relist,reflags,ldict,toknames): |
| 474 if not relist: return [] |
| 475 regex = "|".join(relist) |
| 476 try: |
| 477 lexre = re.compile(regex,re.VERBOSE | reflags) |
| 478 |
| 479 # Build the index to function map for the matching engine |
| 480 lexindexfunc = [ None ] * (max(lexre.groupindex.values())+1) |
| 481 lexindexnames = lexindexfunc[:] |
| 482 |
| 483 for f,i in lexre.groupindex.items(): |
| 484 handle = ldict.get(f,None) |
| 485 if type(handle) in (types.FunctionType, types.MethodType): |
| 486 lexindexfunc[i] = (handle,toknames[f]) |
| 487 lexindexnames[i] = f |
| 488 elif handle is not None: |
| 489 lexindexnames[i] = f |
| 490 if f.find("ignore_") > 0: |
| 491 lexindexfunc[i] = (None,None) |
| 492 else: |
| 493 lexindexfunc[i] = (None, toknames[f]) |
| 494 |
| 495 return [(lexre,lexindexfunc)],[regex],[lexindexnames] |
| 496 except Exception: |
| 497 m = int(len(relist)/2) |
| 498 if m == 0: m = 1 |
| 499 llist, lre, lnames = _form_master_re(relist[:m],reflags,ldict,toknames) |
| 500 rlist, rre, rnames = _form_master_re(relist[m:],reflags,ldict,toknames) |
| 501 return llist+rlist, lre+rre, lnames+rnames |
| 502 |
| 503 # ----------------------------------------------------------------------------- |
| 504 # def _statetoken(s,names) |
| 505 # |
| 506 # Given a declaration name s of the form "t_" and a dictionary whose keys are |
| 507 # state names, this function returns a tuple (states,tokenname) where states |
| 508 # is a tuple of state names and tokenname is the name of the token. For example
, |
| 509 # calling this with s = "t_foo_bar_SPAM" might return (('foo','bar'),'SPAM') |
| 510 # ----------------------------------------------------------------------------- |
| 511 |
| 512 def _statetoken(s,names): |
| 513 nonstate = 1 |
| 514 parts = s.split("_") |
| 515 for i in range(1,len(parts)): |
| 516 if not parts[i] in names and parts[i] != 'ANY': break |
| 517 if i > 1: |
| 518 states = tuple(parts[1:i]) |
| 519 else: |
| 520 states = ('INITIAL',) |
| 521 |
| 522 if 'ANY' in states: |
| 523 states = tuple(names) |
| 524 |
| 525 tokenname = "_".join(parts[i:]) |
| 526 return (states,tokenname) |
| 527 |
| 528 |
| 529 # ----------------------------------------------------------------------------- |
| 530 # LexerReflect() |
| 531 # |
| 532 # This class represents information needed to build a lexer as extracted from a |
| 533 # user's input file. |
| 534 # ----------------------------------------------------------------------------- |
| 535 class LexerReflect(object): |
| 536 def __init__(self,ldict,log=None,reflags=0): |
| 537 self.ldict = ldict |
| 538 self.error_func = None |
| 539 self.tokens = [] |
| 540 self.reflags = reflags |
| 541 self.stateinfo = { 'INITIAL' : 'inclusive'} |
| 542 self.files = {} |
| 543 self.error = 0 |
| 544 |
| 545 if log is None: |
| 546 self.log = PlyLogger(sys.stderr) |
| 547 else: |
| 548 self.log = log |
| 549 |
| 550 # Get all of the basic information |
| 551 def get_all(self): |
| 552 self.get_tokens() |
| 553 self.get_literals() |
| 554 self.get_states() |
| 555 self.get_rules() |
| 556 |
| 557 # Validate all of the information |
| 558 def validate_all(self): |
| 559 self.validate_tokens() |
| 560 self.validate_literals() |
| 561 self.validate_rules() |
| 562 return self.error |
| 563 |
| 564 # Get the tokens map |
| 565 def get_tokens(self): |
| 566 tokens = self.ldict.get("tokens",None) |
| 567 if not tokens: |
| 568 self.log.error("No token list is defined") |
| 569 self.error = 1 |
| 570 return |
| 571 |
| 572 if not isinstance(tokens,(list, tuple)): |
| 573 self.log.error("tokens must be a list or tuple") |
| 574 self.error = 1 |
| 575 return |
| 576 |
| 577 if not tokens: |
| 578 self.log.error("tokens is empty") |
| 579 self.error = 1 |
| 580 return |
| 581 |
| 582 self.tokens = tokens |
| 583 |
| 584 # Validate the tokens |
| 585 def validate_tokens(self): |
| 586 terminals = {} |
| 587 for n in self.tokens: |
| 588 if not _is_identifier.match(n): |
| 589 self.log.error("Bad token name '%s'",n) |
| 590 self.error = 1 |
| 591 if n in terminals: |
| 592 self.log.warning("Token '%s' multiply defined", n) |
| 593 terminals[n] = 1 |
| 594 |
| 595 # Get the literals specifier |
| 596 def get_literals(self): |
| 597 self.literals = self.ldict.get("literals","") |
| 598 |
| 599 # Validate literals |
| 600 def validate_literals(self): |
| 601 try: |
| 602 for c in self.literals: |
| 603 if not isinstance(c,StringTypes) or len(c) > 1: |
| 604 self.log.error("Invalid literal %s. Must be a single charact
er", repr(c)) |
| 605 self.error = 1 |
| 606 continue |
| 607 |
| 608 except TypeError: |
| 609 self.log.error("Invalid literals specification. literals must be a s
equence of characters") |
| 610 self.error = 1 |
| 611 |
| 612 def get_states(self): |
| 613 self.states = self.ldict.get("states",None) |
| 614 # Build statemap |
| 615 if self.states: |
| 616 if not isinstance(self.states,(tuple,list)): |
| 617 self.log.error("states must be defined as a tuple or list") |
| 618 self.error = 1 |
| 619 else: |
| 620 for s in self.states: |
| 621 if not isinstance(s,tuple) or len(s) != 2: |
| 622 self.log.error("Invalid state specifier %s. Must
be a tuple (statename,'exclusive|inclusive')",repr(s)) |
| 623 self.error = 1 |
| 624 continue |
| 625 name, statetype = s |
| 626 if not isinstance(name,StringTypes): |
| 627 self.log.error("State name %s must be a string",
repr(name)) |
| 628 self.error = 1 |
| 629 continue |
| 630 if not (statetype == 'inclusive' or statetype == 'exclus
ive'): |
| 631 self.log.error("State type for state %s must be '
inclusive' or 'exclusive'",name) |
| 632 self.error = 1 |
| 633 continue |
| 634 if name in self.stateinfo: |
| 635 self.log.error("State '%s' already defined",name) |
| 636 self.error = 1 |
| 637 continue |
| 638 self.stateinfo[name] = statetype |
| 639 |
| 640 # Get all of the symbols with a t_ prefix and sort them into various |
| 641 # categories (functions, strings, error functions, and ignore characters) |
| 642 |
| 643 def get_rules(self): |
| 644 tsymbols = [f for f in self.ldict if f[:2] == 't_' ] |
| 645 |
| 646 # Now build up a list of functions and a list of strings |
| 647 |
| 648 self.toknames = { } # Mapping of symbols to token names |
| 649 self.funcsym = { } # Symbols defined as functions |
| 650 self.strsym = { } # Symbols defined as strings |
| 651 self.ignore = { } # Ignore strings by state |
| 652 self.errorf = { } # Error functions by state |
| 653 |
| 654 for s in self.stateinfo: |
| 655 self.funcsym[s] = [] |
| 656 self.strsym[s] = [] |
| 657 |
| 658 if len(tsymbols) == 0: |
| 659 self.log.error("No rules of the form t_rulename are defined") |
| 660 self.error = 1 |
| 661 return |
| 662 |
| 663 for f in tsymbols: |
| 664 t = self.ldict[f] |
| 665 states, tokname = _statetoken(f,self.stateinfo) |
| 666 self.toknames[f] = tokname |
| 667 |
| 668 if hasattr(t,"__call__"): |
| 669 if tokname == 'error': |
| 670 for s in states: |
| 671 self.errorf[s] = t |
| 672 elif tokname == 'ignore': |
| 673 line = func_code(t).co_firstlineno |
| 674 file = func_code(t).co_filename |
| 675 self.log.error("%s:%d: Rule '%s' must be defined as a string
",file,line,t.__name__) |
| 676 self.error = 1 |
| 677 else: |
| 678 for s in states: |
| 679 self.funcsym[s].append((f,t)) |
| 680 elif isinstance(t, StringTypes): |
| 681 if tokname == 'ignore': |
| 682 for s in states: |
| 683 self.ignore[s] = t |
| 684 if "\\" in t: |
| 685 self.log.warning("%s contains a literal backslash '\\'",
f) |
| 686 |
| 687 elif tokname == 'error': |
| 688 self.log.error("Rule '%s' must be defined as a function", f) |
| 689 self.error = 1 |
| 690 else: |
| 691 for s in states: |
| 692 self.strsym[s].append((f,t)) |
| 693 else: |
| 694 self.log.error("%s not defined as a function or string", f) |
| 695 self.error = 1 |
| 696 |
| 697 # Sort the functions by line number |
| 698 for f in self.funcsym.values(): |
| 699 if sys.version_info[0] < 3: |
| 700 f.sort(lambda x,y: cmp(func_code(x[1]).co_firstlineno,func_code(
y[1]).co_firstlineno)) |
| 701 else: |
| 702 # Python 3.0 |
| 703 f.sort(key=lambda x: func_code(x[1]).co_firstlineno) |
| 704 |
| 705 # Sort the strings by regular expression length |
| 706 for s in self.strsym.values(): |
| 707 if sys.version_info[0] < 3: |
| 708 s.sort(lambda x,y: (len(x[1]) < len(y[1])) - (len(x[1]) > len(y[
1]))) |
| 709 else: |
| 710 # Python 3.0 |
| 711 s.sort(key=lambda x: len(x[1]),reverse=True) |
| 712 |
| 713 # Validate all of the t_rules collected |
| 714 def validate_rules(self): |
| 715 for state in self.stateinfo: |
| 716 # Validate all rules defined by functions |
| 717 |
| 718 |
| 719 |
| 720 for fname, f in self.funcsym[state]: |
| 721 line = func_code(f).co_firstlineno |
| 722 file = func_code(f).co_filename |
| 723 self.files[file] = 1 |
| 724 |
| 725 tokname = self.toknames[fname] |
| 726 if isinstance(f, types.MethodType): |
| 727 reqargs = 2 |
| 728 else: |
| 729 reqargs = 1 |
| 730 nargs = func_code(f).co_argcount |
| 731 if nargs > reqargs: |
| 732 self.log.error("%s:%d: Rule '%s' has too many arguments",fil
e,line,f.__name__) |
| 733 self.error = 1 |
| 734 continue |
| 735 |
| 736 if nargs < reqargs: |
| 737 self.log.error("%s:%d: Rule '%s' requires an argument", file
,line,f.__name__) |
| 738 self.error = 1 |
| 739 continue |
| 740 |
| 741 if not f.__doc__: |
| 742 self.log.error("%s:%d: No regular expression defined for rul
e '%s'",file,line,f.__name__) |
| 743 self.error = 1 |
| 744 continue |
| 745 |
| 746 try: |
| 747 c = re.compile("(?P<%s>%s)" % (fname,f.__doc__), re.VERBOSE
| self.reflags) |
| 748 if c.match(""): |
| 749 self.log.error("%s:%d: Regular expression for rule '%s'
matches empty string", file,line,f.__name__) |
| 750 self.error = 1 |
| 751 except re.error: |
| 752 _etype, e, _etrace = sys.exc_info() |
| 753 self.log.error("%s:%d: Invalid regular expression for rule '
%s'. %s", file,line,f.__name__,e) |
| 754 if '#' in f.__doc__: |
| 755 self.log.error("%s:%d. Make sure '#' in rule '%s' is esc
aped with '\\#'",file,line, f.__name__) |
| 756 self.error = 1 |
| 757 |
| 758 # Validate all rules defined by strings |
| 759 for name,r in self.strsym[state]: |
| 760 tokname = self.toknames[name] |
| 761 if tokname == 'error': |
| 762 self.log.error("Rule '%s' must be defined as a function", na
me) |
| 763 self.error = 1 |
| 764 continue |
| 765 |
| 766 if not tokname in self.tokens and tokname.find("ignore_") < 0: |
| 767 self.log.error("Rule '%s' defined for an unspecified token %
s",name,tokname) |
| 768 self.error = 1 |
| 769 continue |
| 770 |
| 771 try: |
| 772 c = re.compile("(?P<%s>%s)" % (name,r),re.VERBOSE | self.ref
lags) |
| 773 if (c.match("")): |
| 774 self.log.error("Regular expression for rule '%s' matche
s empty string",name) |
| 775 self.error = 1 |
| 776 except re.error: |
| 777 _etype, e, _etrace = sys.exc_info() |
| 778 self.log.error("Invalid regular expression for rule '%s'. %s
",name,e) |
| 779 if '#' in r: |
| 780 self.log.error("Make sure '#' in rule '%s' is escaped w
ith '\\#'",name) |
| 781 self.error = 1 |
| 782 |
| 783 if not self.funcsym[state] and not self.strsym[state]: |
| 784 self.log.error("No rules defined for state '%s'",state) |
| 785 self.error = 1 |
| 786 |
| 787 # Validate the error function |
| 788 efunc = self.errorf.get(state,None) |
| 789 if efunc: |
| 790 f = efunc |
| 791 line = func_code(f).co_firstlineno |
| 792 file = func_code(f).co_filename |
| 793 self.files[file] = 1 |
| 794 |
| 795 if isinstance(f, types.MethodType): |
| 796 reqargs = 2 |
| 797 else: |
| 798 reqargs = 1 |
| 799 nargs = func_code(f).co_argcount |
| 800 if nargs > reqargs: |
| 801 self.log.error("%s:%d: Rule '%s' has too many arguments",fil
e,line,f.__name__) |
| 802 self.error = 1 |
| 803 |
| 804 if nargs < reqargs: |
| 805 self.log.error("%s:%d: Rule '%s' requires an argument", file
,line,f.__name__) |
| 806 self.error = 1 |
| 807 |
| 808 for f in self.files: |
| 809 self.validate_file(f) |
| 810 |
| 811 |
| 812 # --------------------------------------------------------------------------
--- |
| 813 # validate_file() |
| 814 # |
| 815 # This checks to see if there are duplicated t_rulename() functions or strin
gs |
| 816 # in the parser input file. This is done using a simple regular expression |
| 817 # match on each line in the given file. |
| 818 # --------------------------------------------------------------------------
--- |
| 819 |
| 820 def validate_file(self,filename): |
| 821 import os.path |
| 822 base,ext = os.path.splitext(filename) |
| 823 if ext != '.py': return # No idea what the file is. Return OK |
| 824 |
| 825 try: |
| 826 f = open(filename) |
| 827 lines = f.readlines() |
| 828 f.close() |
| 829 except IOError: |
| 830 return # Couldn't find the file. Don't worry a
bout it |
| 831 |
| 832 fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(') |
| 833 sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=') |
| 834 |
| 835 counthash = { } |
| 836 linen = 1 |
| 837 for l in lines: |
| 838 m = fre.match(l) |
| 839 if not m: |
| 840 m = sre.match(l) |
| 841 if m: |
| 842 name = m.group(1) |
| 843 prev = counthash.get(name) |
| 844 if not prev: |
| 845 counthash[name] = linen |
| 846 else: |
| 847 self.log.error("%s:%d: Rule %s redefined. Previously defined
on line %d",filename,linen,name,prev) |
| 848 self.error = 1 |
| 849 linen += 1 |
| 850 |
| 851 # ----------------------------------------------------------------------------- |
| 852 # lex(module) |
| 853 # |
| 854 # Build all of the regular expression rules from definitions in the supplied mod
ule |
| 855 # ----------------------------------------------------------------------------- |
| 856 def lex(module=None,object=None,debug=0,optimize=0,lextab="lextab",reflags=0,now
arn=0,outputdir="", debuglog=None, errorlog=None): |
| 857 global lexer |
| 858 ldict = None |
| 859 stateinfo = { 'INITIAL' : 'inclusive'} |
| 860 lexobj = Lexer() |
| 861 lexobj.lexoptimize = optimize |
| 862 global token,input |
| 863 |
| 864 if errorlog is None: |
| 865 errorlog = PlyLogger(sys.stderr) |
| 866 |
| 867 if debug: |
| 868 if debuglog is None: |
| 869 debuglog = PlyLogger(sys.stderr) |
| 870 |
| 871 # Get the module dictionary used for the lexer |
| 872 if object: module = object |
| 873 |
| 874 if module: |
| 875 _items = [(k,getattr(module,k)) for k in dir(module)] |
| 876 ldict = dict(_items) |
| 877 else: |
| 878 ldict = get_caller_module_dict(2) |
| 879 |
| 880 # Collect parser information from the dictionary |
| 881 linfo = LexerReflect(ldict,log=errorlog,reflags=reflags) |
| 882 linfo.get_all() |
| 883 if not optimize: |
| 884 if linfo.validate_all(): |
| 885 raise SyntaxError("Can't build lexer") |
| 886 |
| 887 if optimize and lextab: |
| 888 try: |
| 889 lexobj.readtab(lextab,ldict) |
| 890 token = lexobj.token |
| 891 input = lexobj.input |
| 892 lexer = lexobj |
| 893 return lexobj |
| 894 |
| 895 except ImportError: |
| 896 pass |
| 897 |
| 898 # Dump some basic debugging information |
| 899 if debug: |
| 900 debuglog.info("lex: tokens = %r", linfo.tokens) |
| 901 debuglog.info("lex: literals = %r", linfo.literals) |
| 902 debuglog.info("lex: states = %r", linfo.stateinfo) |
| 903 |
| 904 # Build a dictionary of valid token names |
| 905 lexobj.lextokens = { } |
| 906 for n in linfo.tokens: |
| 907 lexobj.lextokens[n] = 1 |
| 908 |
| 909 # Get literals specification |
| 910 if isinstance(linfo.literals,(list,tuple)): |
| 911 lexobj.lexliterals = type(linfo.literals[0])().join(linfo.literals) |
| 912 else: |
| 913 lexobj.lexliterals = linfo.literals |
| 914 |
| 915 # Get the stateinfo dictionary |
| 916 stateinfo = linfo.stateinfo |
| 917 |
| 918 regexs = { } |
| 919 # Build the master regular expressions |
| 920 for state in stateinfo: |
| 921 regex_list = [] |
| 922 |
| 923 # Add rules defined by functions first |
| 924 for fname, f in linfo.funcsym[state]: |
| 925 line = func_code(f).co_firstlineno |
| 926 file = func_code(f).co_filename |
| 927 regex_list.append("(?P<%s>%s)" % (fname,f.__doc__)) |
| 928 if debug: |
| 929 debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",fname,f
.__doc__, state) |
| 930 |
| 931 # Now add all of the simple rules |
| 932 for name,r in linfo.strsym[state]: |
| 933 regex_list.append("(?P<%s>%s)" % (name,r)) |
| 934 if debug: |
| 935 debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",name,r,
state) |
| 936 |
| 937 regexs[state] = regex_list |
| 938 |
| 939 # Build the master regular expressions |
| 940 |
| 941 if debug: |
| 942 debuglog.info("lex: ==== MASTER REGEXS FOLLOW ====") |
| 943 |
| 944 for state in regexs: |
| 945 lexre, re_text, re_names = _form_master_re(regexs[state],reflags,ldict,l
info.toknames) |
| 946 lexobj.lexstatere[state] = lexre |
| 947 lexobj.lexstateretext[state] = re_text |
| 948 lexobj.lexstaterenames[state] = re_names |
| 949 if debug: |
| 950 for i in range(len(re_text)): |
| 951 debuglog.info("lex: state '%s' : regex[%d] = '%s'",state, i, re_
text[i]) |
| 952 |
| 953 # For inclusive states, we need to add the regular expressions from the INIT
IAL state |
| 954 for state,stype in stateinfo.items(): |
| 955 if state != "INITIAL" and stype == 'inclusive': |
| 956 lexobj.lexstatere[state].extend(lexobj.lexstatere['INITIAL']) |
| 957 lexobj.lexstateretext[state].extend(lexobj.lexstateretext['INITIAL'
]) |
| 958 lexobj.lexstaterenames[state].extend(lexobj.lexstaterenames['INITIA
L']) |
| 959 |
| 960 lexobj.lexstateinfo = stateinfo |
| 961 lexobj.lexre = lexobj.lexstatere["INITIAL"] |
| 962 lexobj.lexretext = lexobj.lexstateretext["INITIAL"] |
| 963 |
| 964 # Set up ignore variables |
| 965 lexobj.lexstateignore = linfo.ignore |
| 966 lexobj.lexignore = lexobj.lexstateignore.get("INITIAL","") |
| 967 |
| 968 # Set up error functions |
| 969 lexobj.lexstateerrorf = linfo.errorf |
| 970 lexobj.lexerrorf = linfo.errorf.get("INITIAL",None) |
| 971 if not lexobj.lexerrorf: |
| 972 errorlog.warning("No t_error rule is defined") |
| 973 |
| 974 # Check state information for ignore and error rules |
| 975 for s,stype in stateinfo.items(): |
| 976 if stype == 'exclusive': |
| 977 if not s in linfo.errorf: |
| 978 errorlog.warning("No error rule is defined for exclusive stat
e '%s'", s) |
| 979 if not s in linfo.ignore and lexobj.lexignore: |
| 980 errorlog.warning("No ignore rule is defined for exclusive sta
te '%s'", s) |
| 981 elif stype == 'inclusive': |
| 982 if not s in linfo.errorf: |
| 983 linfo.errorf[s] = linfo.errorf.get("INITIAL",None) |
| 984 if not s in linfo.ignore: |
| 985 linfo.ignore[s] = linfo.ignore.get("INITIAL","") |
| 986 |
| 987 # Create global versions of the token() and input() functions |
| 988 token = lexobj.token |
| 989 input = lexobj.input |
| 990 lexer = lexobj |
| 991 |
| 992 # If in optimize mode, we write the lextab |
| 993 if lextab and optimize: |
| 994 lexobj.writetab(lextab,outputdir) |
| 995 |
| 996 return lexobj |
| 997 |
| 998 # ----------------------------------------------------------------------------- |
| 999 # runmain() |
| 1000 # |
| 1001 # This runs the lexer as a main program |
| 1002 # ----------------------------------------------------------------------------- |
| 1003 |
| 1004 def runmain(lexer=None,data=None): |
| 1005 if not data: |
| 1006 try: |
| 1007 filename = sys.argv[1] |
| 1008 f = open(filename) |
| 1009 data = f.read() |
| 1010 f.close() |
| 1011 except IndexError: |
| 1012 sys.stdout.write("Reading from standard input (type EOF to end):\n") |
| 1013 data = sys.stdin.read() |
| 1014 |
| 1015 if lexer: |
| 1016 _input = lexer.input |
| 1017 else: |
| 1018 _input = input |
| 1019 _input(data) |
| 1020 if lexer: |
| 1021 _token = lexer.token |
| 1022 else: |
| 1023 _token = token |
| 1024 |
| 1025 while 1: |
| 1026 tok = _token() |
| 1027 if not tok: break |
| 1028 sys.stdout.write("(%s,%r,%d,%d)\n" % (tok.type, tok.value, tok.lineno,to
k.lexpos)) |
| 1029 |
| 1030 # ----------------------------------------------------------------------------- |
| 1031 # @TOKEN(regex) |
| 1032 # |
| 1033 # This decorator function can be used to set the regex expression on a function |
| 1034 # when its docstring might need to be set in an alternative way |
| 1035 # ----------------------------------------------------------------------------- |
| 1036 |
| 1037 def TOKEN(r): |
| 1038 def set_doc(f): |
| 1039 if hasattr(r,"__call__"): |
| 1040 f.__doc__ = r.__doc__ |
| 1041 else: |
| 1042 f.__doc__ = r |
| 1043 return f |
| 1044 return set_doc |
| 1045 |
| 1046 # Alternative spelling of the TOKEN decorator |
| 1047 Token = TOKEN |
| 1048 |
OLD | NEW |