mirror of
https://github.com/python/cpython.git
synced 2024-12-06 00:05:32 +08:00
296 lines
12 KiB
Python
296 lines
12 KiB
Python
"""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."""
|
|
|
|
__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",
|
|
"generate_tokens", "NL"]
|
|
del x
|
|
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 group(*choices) + '*'
|
|
def maybe(*choices): return 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}
|
|
|
|
triple_quoted = {}
|
|
for t in ("'''", '"""',
|
|
"r'''", 'r"""', "R'''", 'R"""',
|
|
"u'''", 'u"""', "U'''", 'U"""',
|
|
"ur'''", 'ur"""', "Ur'''", 'Ur"""',
|
|
"uR'''", 'uR"""', "UR'''", 'UR"""'):
|
|
triple_quoted[t] = t
|
|
single_quoted = {}
|
|
for t in ("'", '"',
|
|
"r'", 'r"', "R'", 'R"',
|
|
"u'", 'u"', "U'", 'U"',
|
|
"ur'", 'ur"', "Ur'", 'Ur"',
|
|
"uR'", 'uR"', "UR'", 'UR"' ):
|
|
single_quoted[t] = t
|
|
|
|
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):
|
|
"""
|
|
The tokenize() function accepts two parameters: one representing the
|
|
input stream, and one providing an output mechanism for tokenize().
|
|
|
|
The first parameter, readline, must be a callable object which provides
|
|
the same interface as the readline() method of built-in file objects.
|
|
Each call to the function should return one line of input as a string.
|
|
|
|
The second parameter, tokeneater, must also be a callable object. It is
|
|
called once for each token, with five arguments, corresponding to the
|
|
tuples generated by generate_tokens().
|
|
"""
|
|
try:
|
|
tokenize_loop(readline, tokeneater)
|
|
except StopTokenizing:
|
|
pass
|
|
|
|
# backwards compatible interface
|
|
def tokenize_loop(readline, tokeneater):
|
|
for token_info in generate_tokens(readline):
|
|
tokeneater(*token_info)
|
|
|
|
def generate_tokens(readline):
|
|
"""
|
|
The generate_tokens() generator requires one argment, readline, which
|
|
must be a callable object which provides the same interface as the
|
|
readline() method of built-in file objects. Each call to the function
|
|
should return one line of input as a string.
|
|
|
|
The generator produces 5-tuples with these members: the token type; the
|
|
token string; a 2-tuple (srow, scol) of ints specifying the row and
|
|
column where the token begins in the source; a 2-tuple (erow, ecol) of
|
|
ints specifying the row and column where the token ends in the source;
|
|
and the line on which the token was found. The line passed is the
|
|
logical line; continuation lines are included.
|
|
"""
|
|
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:
|
|
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 single_quoted or \
|
|
token[:2] in single_quoted or \
|
|
token[:3] in single_quoted:
|
|
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)
|