| """Tokenization help for Python programs. |
| |
| generate_tokens(readline) is a generator that breaks a stream of |
| text into Python tokens. It accepts a readline-like method which is called |
| repeatedly to get the next line of input (or "" for EOF). It generates |
| 5-tuples with these members: |
| |
| the token type (see token.py) |
| the token (a string) |
| the starting (row, column) indices of the token (a 2-tuple of ints) |
| the ending (row, column) indices of the token (a 2-tuple of ints) |
| the original line (string) |
| |
| It is designed to match the working of the Python tokenizer exactly, except |
| that it produces COMMENT tokens for comments and gives type OP for all |
| operators |
| |
| Older entry points |
| tokenize_loop(readline, tokeneater) |
| tokenize(readline, tokeneater=printtoken) |
| are the same, except instead of generating tokens, tokeneater is a callback |
| function to which the 5 fields described above are passed as 5 arguments, |
| each time a new token is found.""" |
| |
| from __future__ import generators |
| |
| __author__ = 'Ka-Ping Yee <ping@lfw.org>' |
| __credits__ = \ |
| 'GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro' |
| |
| import string, re |
| from token import * |
| |
| import token |
| __all__ = [x for x in dir(token) if x[0] != '_'] + ["COMMENT", "tokenize", "NL"] |
| del token |
| |
| COMMENT = N_TOKENS |
| tok_name[COMMENT] = 'COMMENT' |
| NL = N_TOKENS + 1 |
| tok_name[NL] = 'NL' |
| N_TOKENS += 2 |
| |
| def group(*choices): return '(' + '|'.join(choices) + ')' |
| def any(*choices): return apply(group, choices) + '*' |
| def maybe(*choices): return apply(group, choices) + '?' |
| |
| Whitespace = r'[ \f\t]*' |
| Comment = r'#[^\r\n]*' |
| Ignore = Whitespace + any(r'\\\r?\n' + Whitespace) + maybe(Comment) |
| Name = r'[a-zA-Z_]\w*' |
| |
| Hexnumber = r'0[xX][\da-fA-F]*[lL]?' |
| Octnumber = r'0[0-7]*[lL]?' |
| Decnumber = r'[1-9]\d*[lL]?' |
| Intnumber = group(Hexnumber, Octnumber, Decnumber) |
| Exponent = r'[eE][-+]?\d+' |
| Pointfloat = group(r'\d+\.\d*', r'\.\d+') + maybe(Exponent) |
| Expfloat = r'\d+' + Exponent |
| Floatnumber = group(Pointfloat, Expfloat) |
| Imagnumber = group(r'\d+[jJ]', Floatnumber + r'[jJ]') |
| Number = group(Imagnumber, Floatnumber, Intnumber) |
| |
| # Tail end of ' string. |
| Single = r"[^'\\]*(?:\\.[^'\\]*)*'" |
| # Tail end of " string. |
| Double = r'[^"\\]*(?:\\.[^"\\]*)*"' |
| # Tail end of ''' string. |
| Single3 = r"[^'\\]*(?:(?:\\.|'(?!''))[^'\\]*)*'''" |
| # Tail end of """ string. |
| Double3 = r'[^"\\]*(?:(?:\\.|"(?!""))[^"\\]*)*"""' |
| Triple = group("[uU]?[rR]?'''", '[uU]?[rR]?"""') |
| # Single-line ' or " string. |
| String = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*'", |
| r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*"') |
| |
| # Because of leftmost-then-longest match semantics, be sure to put the |
| # longest operators first (e.g., if = came before ==, == would get |
| # recognized as two instances of =). |
| Operator = group(r"\*\*=?", r">>=?", r"<<=?", r"<>", r"!=", |
| r"//=?", |
| r"[+\-*/%&|^=<>]=?", |
| r"~") |
| |
| Bracket = '[][(){}]' |
| Special = group(r'\r?\n', r'[:;.,`]') |
| Funny = group(Operator, Bracket, Special) |
| |
| PlainToken = group(Number, Funny, String, Name) |
| Token = Ignore + PlainToken |
| |
| # First (or only) line of ' or " string. |
| ContStr = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*" + |
| group("'", r'\\\r?\n'), |
| r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*' + |
| group('"', r'\\\r?\n')) |
| PseudoExtras = group(r'\\\r?\n', Comment, Triple) |
| PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name) |
| |
| tokenprog, pseudoprog, single3prog, double3prog = map( |
| re.compile, (Token, PseudoToken, Single3, Double3)) |
| endprogs = {"'": re.compile(Single), '"': re.compile(Double), |
| "'''": single3prog, '"""': double3prog, |
| "r'''": single3prog, 'r"""': double3prog, |
| "u'''": single3prog, 'u"""': double3prog, |
| "ur'''": single3prog, 'ur"""': double3prog, |
| "R'''": single3prog, 'R"""': double3prog, |
| "U'''": single3prog, 'U"""': double3prog, |
| "uR'''": single3prog, 'uR"""': double3prog, |
| "Ur'''": single3prog, 'Ur"""': double3prog, |
| "UR'''": single3prog, 'UR"""': double3prog, |
| 'r': None, 'R': None, 'u': None, 'U': None} |
| |
| tabsize = 8 |
| |
| class TokenError(Exception): pass |
| |
| class StopTokenizing(Exception): pass |
| |
| def printtoken(type, token, (srow, scol), (erow, ecol), line): # for testing |
| print "%d,%d-%d,%d:\t%s\t%s" % \ |
| (srow, scol, erow, ecol, tok_name[type], repr(token)) |
| |
| def tokenize(readline, tokeneater=printtoken): |
| try: |
| tokenize_loop(readline, tokeneater) |
| except StopTokenizing: |
| pass |
| |
| # backwards compatible interface |
| def tokenize_loop(readline, tokeneater): |
| for token_info in generate_tokens(readline): |
| apply(tokeneater, token_info) |
| |
| def generate_tokens(readline): |
| lnum = parenlev = continued = 0 |
| namechars, numchars = string.ascii_letters + '_', '0123456789' |
| contstr, needcont = '', 0 |
| contline = None |
| indents = [0] |
| |
| while 1: # loop over lines in stream |
| line = readline() |
| lnum = lnum + 1 |
| pos, max = 0, len(line) |
| |
| if contstr: # continued string |
| if not line: |
| raise TokenError, ("EOF in multi-line string", strstart) |
| endmatch = endprog.match(line) |
| if endmatch: |
| pos = end = endmatch.end(0) |
| yield (STRING, contstr + line[:end], |
| strstart, (lnum, end), contline + line) |
| contstr, needcont = '', 0 |
| contline = None |
| elif needcont and line[-2:] != '\\\n' and line[-3:] != '\\\r\n': |
| yield (ERRORTOKEN, contstr + line, |
| strstart, (lnum, len(line)), contline) |
| contstr = '' |
| contline = None |
| continue |
| else: |
| contstr = contstr + line |
| contline = contline + line |
| continue |
| |
| elif parenlev == 0 and not continued: # new statement |
| if not line: break |
| column = 0 |
| while pos < max: # measure leading whitespace |
| if line[pos] == ' ': column = column + 1 |
| elif line[pos] == '\t': column = (column/tabsize + 1)*tabsize |
| elif line[pos] == '\f': column = 0 |
| else: break |
| pos = pos + 1 |
| if pos == max: break |
| |
| if line[pos] in '#\r\n': # skip comments or blank lines |
| yield ((NL, COMMENT)[line[pos] == '#'], line[pos:], |
| (lnum, pos), (lnum, len(line)), line) |
| continue |
| |
| if column > indents[-1]: # count indents or dedents |
| indents.append(column) |
| yield (INDENT, line[:pos], (lnum, 0), (lnum, pos), line) |
| while column < indents[-1]: |
| indents = indents[:-1] |
| yield (DEDENT, '', (lnum, pos), (lnum, pos), line) |
| |
| else: # continued statement |
| if not line: |
| raise TokenError, ("EOF in multi-line statement", (lnum, 0)) |
| continued = 0 |
| |
| while pos < max: |
| pseudomatch = pseudoprog.match(line, pos) |
| if pseudomatch: # scan for tokens |
| start, end = pseudomatch.span(1) |
| spos, epos, pos = (lnum, start), (lnum, end), end |
| token, initial = line[start:end], line[start] |
| |
| if initial in numchars or \ |
| (initial == '.' and token != '.'): # ordinary number |
| yield (NUMBER, token, spos, epos, line) |
| elif initial in '\r\n': |
| yield (parenlev > 0 and NL or NEWLINE, |
| token, spos, epos, line) |
| elif initial == '#': |
| yield (COMMENT, token, spos, epos, line) |
| elif token in ("'''", '"""', # triple-quoted |
| "r'''", 'r"""', "R'''", 'R"""', |
| "u'''", 'u"""', "U'''", 'U"""', |
| "ur'''", 'ur"""', "Ur'''", 'Ur"""', |
| "uR'''", 'uR"""', "UR'''", 'UR"""'): |
| endprog = endprogs[token] |
| endmatch = endprog.match(line, pos) |
| if endmatch: # all on one line |
| pos = endmatch.end(0) |
| token = line[start:pos] |
| yield (STRING, token, spos, (lnum, pos), line) |
| else: |
| strstart = (lnum, start) # multiple lines |
| contstr = line[start:] |
| contline = line |
| break |
| elif initial in ("'", '"') or \ |
| token[:2] in ("r'", 'r"', "R'", 'R"', |
| "u'", 'u"', "U'", 'U"') or \ |
| token[:3] in ("ur'", 'ur"', "Ur'", 'Ur"', |
| "uR'", 'uR"', "UR'", 'UR"' ): |
| if token[-1] == '\n': # continued string |
| strstart = (lnum, start) |
| endprog = (endprogs[initial] or endprogs[token[1]] or |
| endprogs[token[2]]) |
| contstr, needcont = line[start:], 1 |
| contline = line |
| break |
| else: # ordinary string |
| yield (STRING, token, spos, epos, line) |
| elif initial in namechars: # ordinary name |
| yield (NAME, token, spos, epos, line) |
| elif initial == '\\': # continued stmt |
| continued = 1 |
| else: |
| if initial in '([{': parenlev = parenlev + 1 |
| elif initial in ')]}': parenlev = parenlev - 1 |
| yield (OP, token, spos, epos, line) |
| else: |
| yield (ERRORTOKEN, line[pos], |
| (lnum, pos), (lnum, pos+1), line) |
| pos = pos + 1 |
| |
| for indent in indents[1:]: # pop remaining indent levels |
| yield (DEDENT, '', (lnum, 0), (lnum, 0), '') |
| yield (ENDMARKER, '', (lnum, 0), (lnum, 0), '') |
| |
| if __name__ == '__main__': # testing |
| import sys |
| if len(sys.argv) > 1: tokenize(open(sys.argv[1]).readline) |
| else: tokenize(sys.stdin.readline) |