Ka-Ping's muich improved version of March 26, 1997:

#     Ignore now accepts \f as whitespace.  Operator now includes '**'.
#     Ignore and Special now accept \n or \r\n at the end of a line.
#     Imagnumber is new.  Expfloat is corrected to reject '0e4'.
This commit is contained in:
Guido van Rossum 1997-04-08 14:24:39 +00:00
parent 24dacb38c5
commit 1aec32363f
1 changed files with 96 additions and 72 deletions

View File

@ -1,158 +1,182 @@
"""Tokenization help for Python programs.
This module compiles a regular expression that recognizes Python
tokens in individual lines of text. The regular expression handles
everything except indentation, continuations, and triple-quoted
strings. The function 'tokenize.tokenize()' takes care of these
things for streams of text. It accepts a readline-like function which
is called repeatedly to come up with the next input line (or "" for
EOF), and a "token-eater" function which is called for each token
found, passing its type, a string containing the token, the line
number, the line, and the starting and ending positions of the token
within the line. It is designed to match the working of the Python
tokenizer exactly.
This module exports a function called 'tokenize()' 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) and a "token-eater"
function which is called once for each token found. The latter function is
passed the token type, a string containing the token, the starting and
ending (row, column) coordinates of the token, and the original line. 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.
"""
For compatibility with the older 'tokenize' module, this also compiles a
regular expression into 'tokenprog' that matches Python tokens in individual
lines of text, leaving the token in 'tokenprog.group(3)', but does not
handle indentation, continuations, or multi-line strings."""
__version__ = "Ka-Ping Yee, 4 March 1997, updated by GvR, 10 March 1997"
__version__ = "Ka-Ping Yee, 26 March 1997"
import string, regex
from token import *
COMMENT = N_TOKENS
tok_name[COMMENT] = 'COMMENT'
# Changes from 1.3:
# Ignore now accepts \f as whitespace. Operator now includes '**'.
# Ignore and Special now accept \n or \r\n at the end of a line.
# Imagnumber is new. Expfloat is corrected to reject '0e4'.
# Note: to get a quoted backslash in a regex, it must be enclosed in brackets.
def group(*choices): return '\(' + string.join(choices, '\|') + '\)'
Ignore = '[ \f\t]*\([\]\r?\n[ \t]*\)*\(#.*\)?'
Whitespace = '[ \f\t]*'
Comment = '\(#[^\r\n]*\)'
Ignore = Whitespace + group('[\]\r?\n' + Whitespace)+'*' + Comment+'?'
Name = '[a-zA-Z_][a-zA-Z0-9_]*'
ImagZero = '0[jJ]' # This is not caught by any of the following
Hexnumber = '0[xX][0-9a-fA-F]*[lL]?'
Octnumber = '0[0-7]*[lL]?'
Decnumber = '[1-9][0-9]*[lLjJ]?'
Intnumber = group(ImagZero, Hexnumber, Octnumber, Decnumber)
Decnumber = '[1-9][0-9]*[lL]?'
Intnumber = group(Hexnumber, Octnumber, Decnumber)
Exponent = '[eE][-+]?[0-9]+'
Pointfloat = group('[0-9]+\.[0-9]*', '\.[0-9]+') + group(Exponent) + '?'
Expfloat = '[0-9]+' + Exponent
Floatnumber = group(Pointfloat, Expfloat) + "[jJ]?"
Number = group(Floatnumber, Intnumber)
Expfloat = '[1-9][0-9]*' + Exponent
Floatnumber = group(Pointfloat, Expfloat)
Imagnumber = group('0[jJ]', '[1-9][0-9]*[jJ]', Floatnumber + '[jJ]')
Number = group(Imagnumber, Floatnumber, Intnumber)
Single = group('^\'', '[^\]\'')
Single = group("^'", "[^\]'")
Double = group('^"', '[^\]"')
Tsingle = group('^\'\'\'', '[^\]\'\'\'')
Tdouble = group('^"""', '[^\]"""')
Triple = group('\'\'\'', '"""')
String = group('\'' + group('[\].', '[^\'\]')+ '*' + group('\'', '[\]\n'),
'"' + group('[\].', '[^"\]') + '*' + group('"', '[\]\n'))
Single3 = group("^'''", "[^\]'''")
Double3 = group('^"""', '[^\]"""')
Triple = group("'''", '"""')
String = group("'" + group('[\].', "[^\n'\]") + "*'",
'"' + group('[\].', '[^\n"\]') + '*"')
Operator = group('\+', '\-', '\*\*', '\*', '\^', '~', '/', '%', '&', '|',
'<<', '>>', '==', '<=', '<>', '!=', '>=', '=', '<', '>')
Bracket = '[][(){}]'
Special = group('[\]?\r?\n', '[:;.,`\f]')
Special = group('\r?\n', '[:;.,`]')
Funny = group(Operator, Bracket, Special)
PlainToken = group(Name, Number, Triple, String, Funny)
PlainToken = group(Name, Number, String, Funny)
Token = Ignore + PlainToken
ContStr = group("'" + group('[\].', "[^\n'\]")+'*' + group("'", '[\]\r?\n'),
'"' + group('[\].', '[^\n"\]')+'*' + group('"', '[\]\r?\n'))
PseudoExtras = group('[\]\r?\n', Comment, Triple)
PseudoToken = Whitespace + group(PseudoExtras, Name, Number, ContStr, Funny)
try:
save_syntax = regex.set_syntax(0) # use default syntax
saved_syntax = regex.set_syntax(0) # use default syntax
tokenprog = regex.compile(Token)
pseudoprog = regex.compile(PseudoToken)
endprogs = { '\'': regex.compile(Single), '"': regex.compile(Double),
'\'\'\'': regex.compile(Tsingle), '"""': regex.compile(Tdouble) }
'\'\'\'': regex.compile(Single3), '"""': regex.compile(Double3) }
finally:
regex.set_syntax(save_syntax) # restore original syntax
regex.set_syntax(saved_syntax) # restore original syntax
tabsize = 8
TokenError = 'TokenError'
def printtoken(type, string, linenum, line, start, end): # for testing
print `linenum` + ':', tok_name[type], repr(string)
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):
linenum = parenlev = continued = 0
def tokenize(readline, tokeneater=printtoken):
lnum = parenlev = continued = 0
namechars, numchars = string.letters + '_', string.digits
contstr = ''
indents = [0]
while 1: # loop over lines in stream
line = readline()
linenum = linenum + 1
if line[-2:] == '\r\n': line = line[:-2] + '\n'
lnum = lnum + 1
pos, max = 0, len(line)
if contstr: # continued string
if not line: raise TokenError, "EOF within multi-line string"
if contstr[-2:] == '\\\n': contstr = contstr[:-2] + '\n'
if endprog.search(line) >= 0:
pos = end = endprog.regs[0][1]
tokeneater(STRING, contstr + line[:end], linenum, line, 0, 0)
tokeneater(STRING, contstr + line[:end],
strstart, (lnum, end), line)
contstr = ''
else:
contstr = contstr + line
continue
elif parenlev == 0 and not continued: # this is a new statement
elif parenlev == 0 and not continued: # new statement
if not line: break
column = 0
while 1: # measure leading whitespace
while pos < max: # measure leading whitespace
if line[pos] == ' ': column = column + 1
elif line[pos] == '\t': column = (column/tabsize + 1) * tabsize
elif line[pos] == '\t': column = (column/tabsize + 1)*tabsize
elif line[pos] == '\f': column = 0
else: break
pos = pos + 1
if line[pos] in '#\n': continue # skip comments or blank lines
if pos == max: break
if line[pos] in '#\r\n': # skip comments or blank lines
tokeneater((NEWLINE, COMMENT)[line[pos] == '#'], line[pos:],
(lnum, pos), (lnum, len(line)), line)
continue
if column > indents[-1]: # count indents or dedents
indents.append(column)
tokeneater(INDENT, '\t', linenum, line, 0, 0)
tokeneater(INDENT, line[:pos], (lnum, 0), (lnum, pos), line)
while column < indents[-1]:
indents = indents[:-1]
tokeneater(DEDENT, '\t', linenum, line, 0, 0)
tokeneater(DEDENT, line[:pos], (lnum, 0), (lnum, pos), line)
else: # continued statement
if not line: raise TokenError, "EOF within multi-line statement"
continued = 0
while pos < max:
if tokenprog.match(line, pos) > 0: # scan for tokens
start, end = tokenprog.regs[3]
token = line[start:end]
if pseudoprog.match(line, pos) > 0: # scan for tokens
start, end = pseudoprog.regs[1]
spos, epos = (lnum, start), (lnum, end)
token, initial = line[start:end], line[start]
pos = end
if token[0] in namechars: # ordinary name
tokeneater(NAME, token, linenum, line, start, end)
elif token[0] in numchars: # ordinary number
tokeneater(NUMBER, token, linenum, line, start, end)
if initial in namechars: # ordinary name
tokeneater(NAME, token, spos, epos, line)
elif initial in numchars: # ordinary number
tokeneater(NUMBER, token, spos, epos, line)
elif initial in '\r\n':
tokeneater(NEWLINE, token, spos, epos, line)
elif initial == '#':
tokeneater(COMMENT, token, spos, epos, line)
elif initial == '\\': # continued stmt
continued = 1
elif token in ('\'\'\'', '"""'): # triple-quoted
endprog = endprogs[token]
if endprog.search(line, pos) >= 0: # all on one line
pos = endprog.regs[0][1]
token = line[start:pos]
tokeneater(STRING, token, linenum, line, start, pos)
tokeneater(STRING, token, spos, (lnum, pos), line)
else:
contstr = line[start:] # multiple lines
strstart = (lnum, start) # multiple lines
contstr = line[start:]
break
elif token[0] in '\'"':
elif initial in '\'"':
if token[-1] == '\n': # continued string
endprog, contstr = endprogs[token[0]], line[start:]
strstart = (lnum, start)
endprog, contstr = endprogs[initial], line[start:]
break
else: # ordinary string
tokeneater(STRING, token, linenum, line, start, end)
elif token[0] == '\n':
tokeneater(NEWLINE, token, linenum, line, start, end)
elif token[0] == '\\': # continued stmt
continued = 1
tokeneater(STRING, token, spos, epos, line)
else:
if token[0] in '([{': parenlev = parenlev + 1
if token[0] in ')]}': parenlev = parenlev - 1
tokeneater(OP, token, linenum, line, start, end)
if initial in '([{': parenlev = parenlev + 1
elif initial in ')]}': parenlev = parenlev - 1
tokeneater(OP, token, spos, epos, line)
else:
tokeneater(ERRORTOKEN, line[pos], linenum, line, pos, pos + 1)
tokeneater(ERRORTOKEN, line[pos], spos, (lnum, pos+1), line)
pos = pos + 1
for indent in indents[1:]: # pop remaining indent levels
tokeneater(DEDENT, '\t', linenum, line, 0, 0)
tokeneater(DEDENT, '', (lnum, 0), (lnum, 0), '')
if __name__ == '__main__': # testing
import sys
file = open(sys.argv[-1])
tokenize(file.readline)
tokenize(open(sys.argv[-1]).readline)