[2] | 1 | """A collection of string operations (most are no longer used).
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| 2 |
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| 3 | Warning: most of the code you see here isn't normally used nowadays.
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| 4 | Beginning with Python 1.6, many of these functions are implemented as
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| 5 | methods on the standard string object. They used to be implemented by
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| 6 | a built-in module called strop, but strop is now obsolete itself.
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| 7 |
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| 8 | Public module variables:
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| 9 |
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| 10 | whitespace -- a string containing all characters considered whitespace
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| 11 | lowercase -- a string containing all characters considered lowercase letters
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| 12 | uppercase -- a string containing all characters considered uppercase letters
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| 13 | letters -- a string containing all characters considered letters
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| 14 | digits -- a string containing all characters considered decimal digits
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| 15 | hexdigits -- a string containing all characters considered hexadecimal digits
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| 16 | octdigits -- a string containing all characters considered octal digits
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| 17 | punctuation -- a string containing all characters considered punctuation
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| 18 | printable -- a string containing all characters considered printable
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| 19 |
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| 20 | """
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| 21 |
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| 22 | # Some strings for ctype-style character classification
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| 23 | whitespace = ' \t\n\r\v\f'
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| 24 | lowercase = 'abcdefghijklmnopqrstuvwxyz'
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| 25 | uppercase = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
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| 26 | letters = lowercase + uppercase
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| 27 | ascii_lowercase = lowercase
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| 28 | ascii_uppercase = uppercase
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| 29 | ascii_letters = ascii_lowercase + ascii_uppercase
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| 30 | digits = '0123456789'
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| 31 | hexdigits = digits + 'abcdef' + 'ABCDEF'
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| 32 | octdigits = '01234567'
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| 33 | punctuation = """!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"""
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| 34 | printable = digits + letters + punctuation + whitespace
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| 35 |
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| 36 | # Case conversion helpers
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| 37 | # Use str to convert Unicode literal in case of -U
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| 38 | l = map(chr, xrange(256))
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| 39 | _idmap = str('').join(l)
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| 40 | del l
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| 41 |
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| 42 | # Functions which aren't available as string methods.
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| 43 |
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| 44 | # Capitalize the words in a string, e.g. " aBc dEf " -> "Abc Def".
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| 45 | def capwords(s, sep=None):
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| 46 | """capwords(s [,sep]) -> string
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| 47 |
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| 48 | Split the argument into words using split, capitalize each
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| 49 | word using capitalize, and join the capitalized words using
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| 50 | join. If the optional second argument sep is absent or None,
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| 51 | runs of whitespace characters are replaced by a single space
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| 52 | and leading and trailing whitespace are removed, otherwise
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| 53 | sep is used to split and join the words.
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| 54 |
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| 55 | """
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| 56 | return (sep or ' ').join(x.capitalize() for x in s.split(sep))
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| 57 |
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| 58 |
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| 59 | # Construct a translation string
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| 60 | _idmapL = None
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| 61 | def maketrans(fromstr, tostr):
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| 62 | """maketrans(frm, to) -> string
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| 63 |
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| 64 | Return a translation table (a string of 256 bytes long)
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| 65 | suitable for use in string.translate. The strings frm and to
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| 66 | must be of the same length.
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| 67 |
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| 68 | """
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| 69 | if len(fromstr) != len(tostr):
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| 70 | raise ValueError, "maketrans arguments must have same length"
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| 71 | global _idmapL
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| 72 | if not _idmapL:
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| 73 | _idmapL = list(_idmap)
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| 74 | L = _idmapL[:]
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| 75 | fromstr = map(ord, fromstr)
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| 76 | for i in range(len(fromstr)):
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| 77 | L[fromstr[i]] = tostr[i]
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| 78 | return ''.join(L)
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| 79 |
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| 80 |
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| 81 |
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| 82 | ####################################################################
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| 83 | import re as _re
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| 84 |
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| 85 | class _multimap:
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| 86 | """Helper class for combining multiple mappings.
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| 87 |
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| 88 | Used by .{safe_,}substitute() to combine the mapping and keyword
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| 89 | arguments.
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| 90 | """
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| 91 | def __init__(self, primary, secondary):
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| 92 | self._primary = primary
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| 93 | self._secondary = secondary
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| 94 |
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| 95 | def __getitem__(self, key):
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| 96 | try:
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| 97 | return self._primary[key]
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| 98 | except KeyError:
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| 99 | return self._secondary[key]
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| 100 |
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| 101 |
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| 102 | class _TemplateMetaclass(type):
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| 103 | pattern = r"""
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| 104 | %(delim)s(?:
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| 105 | (?P<escaped>%(delim)s) | # Escape sequence of two delimiters
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| 106 | (?P<named>%(id)s) | # delimiter and a Python identifier
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| 107 | {(?P<braced>%(id)s)} | # delimiter and a braced identifier
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| 108 | (?P<invalid>) # Other ill-formed delimiter exprs
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| 109 | )
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| 110 | """
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| 111 |
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| 112 | def __init__(cls, name, bases, dct):
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| 113 | super(_TemplateMetaclass, cls).__init__(name, bases, dct)
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| 114 | if 'pattern' in dct:
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| 115 | pattern = cls.pattern
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| 116 | else:
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| 117 | pattern = _TemplateMetaclass.pattern % {
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| 118 | 'delim' : _re.escape(cls.delimiter),
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| 119 | 'id' : cls.idpattern,
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| 120 | }
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| 121 | cls.pattern = _re.compile(pattern, _re.IGNORECASE | _re.VERBOSE)
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| 122 |
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| 123 |
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| 124 | class Template:
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| 125 | """A string class for supporting $-substitutions."""
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| 126 | __metaclass__ = _TemplateMetaclass
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| 127 |
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| 128 | delimiter = '$'
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| 129 | idpattern = r'[_a-z][_a-z0-9]*'
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| 130 |
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| 131 | def __init__(self, template):
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| 132 | self.template = template
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| 133 |
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| 134 | # Search for $$, $identifier, ${identifier}, and any bare $'s
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| 135 |
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| 136 | def _invalid(self, mo):
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| 137 | i = mo.start('invalid')
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| 138 | lines = self.template[:i].splitlines(True)
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| 139 | if not lines:
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| 140 | colno = 1
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| 141 | lineno = 1
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| 142 | else:
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| 143 | colno = i - len(''.join(lines[:-1]))
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| 144 | lineno = len(lines)
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| 145 | raise ValueError('Invalid placeholder in string: line %d, col %d' %
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| 146 | (lineno, colno))
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| 147 |
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| 148 | def substitute(self, *args, **kws):
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| 149 | if len(args) > 1:
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| 150 | raise TypeError('Too many positional arguments')
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| 151 | if not args:
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| 152 | mapping = kws
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| 153 | elif kws:
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| 154 | mapping = _multimap(kws, args[0])
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| 155 | else:
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| 156 | mapping = args[0]
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| 157 | # Helper function for .sub()
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| 158 | def convert(mo):
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| 159 | # Check the most common path first.
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| 160 | named = mo.group('named') or mo.group('braced')
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| 161 | if named is not None:
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| 162 | val = mapping[named]
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| 163 | # We use this idiom instead of str() because the latter will
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| 164 | # fail if val is a Unicode containing non-ASCII characters.
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| 165 | return '%s' % (val,)
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| 166 | if mo.group('escaped') is not None:
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| 167 | return self.delimiter
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| 168 | if mo.group('invalid') is not None:
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| 169 | self._invalid(mo)
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| 170 | raise ValueError('Unrecognized named group in pattern',
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| 171 | self.pattern)
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| 172 | return self.pattern.sub(convert, self.template)
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| 173 |
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| 174 | def safe_substitute(self, *args, **kws):
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| 175 | if len(args) > 1:
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| 176 | raise TypeError('Too many positional arguments')
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| 177 | if not args:
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| 178 | mapping = kws
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| 179 | elif kws:
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| 180 | mapping = _multimap(kws, args[0])
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| 181 | else:
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| 182 | mapping = args[0]
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| 183 | # Helper function for .sub()
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| 184 | def convert(mo):
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| 185 | named = mo.group('named')
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| 186 | if named is not None:
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| 187 | try:
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| 188 | # We use this idiom instead of str() because the latter
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| 189 | # will fail if val is a Unicode containing non-ASCII
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| 190 | return '%s' % (mapping[named],)
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| 191 | except KeyError:
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| 192 | return self.delimiter + named
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| 193 | braced = mo.group('braced')
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| 194 | if braced is not None:
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| 195 | try:
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| 196 | return '%s' % (mapping[braced],)
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| 197 | except KeyError:
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| 198 | return self.delimiter + '{' + braced + '}'
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| 199 | if mo.group('escaped') is not None:
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| 200 | return self.delimiter
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| 201 | if mo.group('invalid') is not None:
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| 202 | return self.delimiter
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| 203 | raise ValueError('Unrecognized named group in pattern',
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| 204 | self.pattern)
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| 205 | return self.pattern.sub(convert, self.template)
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| 206 |
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| 207 |
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| 208 |
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| 209 | ####################################################################
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| 210 | # NOTE: Everything below here is deprecated. Use string methods instead.
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| 211 | # This stuff will go away in Python 3.0.
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| 212 |
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| 213 | # Backward compatible names for exceptions
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| 214 | index_error = ValueError
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| 215 | atoi_error = ValueError
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| 216 | atof_error = ValueError
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| 217 | atol_error = ValueError
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| 218 |
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| 219 | # convert UPPER CASE letters to lower case
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| 220 | def lower(s):
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| 221 | """lower(s) -> string
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| 222 |
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| 223 | Return a copy of the string s converted to lowercase.
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| 224 |
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| 225 | """
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| 226 | return s.lower()
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| 227 |
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| 228 | # Convert lower case letters to UPPER CASE
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| 229 | def upper(s):
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| 230 | """upper(s) -> string
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| 231 |
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| 232 | Return a copy of the string s converted to uppercase.
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| 233 |
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| 234 | """
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| 235 | return s.upper()
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| 236 |
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| 237 | # Swap lower case letters and UPPER CASE
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| 238 | def swapcase(s):
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| 239 | """swapcase(s) -> string
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| 240 |
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| 241 | Return a copy of the string s with upper case characters
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| 242 | converted to lowercase and vice versa.
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| 243 |
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| 244 | """
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| 245 | return s.swapcase()
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| 246 |
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| 247 | # Strip leading and trailing tabs and spaces
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| 248 | def strip(s, chars=None):
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| 249 | """strip(s [,chars]) -> string
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| 250 |
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| 251 | Return a copy of the string s with leading and trailing
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| 252 | whitespace removed.
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| 253 | If chars is given and not None, remove characters in chars instead.
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| 254 | If chars is unicode, S will be converted to unicode before stripping.
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| 255 |
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| 256 | """
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| 257 | return s.strip(chars)
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| 258 |
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| 259 | # Strip leading tabs and spaces
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| 260 | def lstrip(s, chars=None):
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| 261 | """lstrip(s [,chars]) -> string
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| 262 |
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| 263 | Return a copy of the string s with leading whitespace removed.
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| 264 | If chars is given and not None, remove characters in chars instead.
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| 265 |
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| 266 | """
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| 267 | return s.lstrip(chars)
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| 268 |
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| 269 | # Strip trailing tabs and spaces
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| 270 | def rstrip(s, chars=None):
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| 271 | """rstrip(s [,chars]) -> string
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| 272 |
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| 273 | Return a copy of the string s with trailing whitespace removed.
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| 274 | If chars is given and not None, remove characters in chars instead.
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| 275 |
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| 276 | """
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| 277 | return s.rstrip(chars)
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| 278 |
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| 279 |
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| 280 | # Split a string into a list of space/tab-separated words
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| 281 | def split(s, sep=None, maxsplit=-1):
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| 282 | """split(s [,sep [,maxsplit]]) -> list of strings
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| 283 |
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| 284 | Return a list of the words in the string s, using sep as the
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| 285 | delimiter string. If maxsplit is given, splits at no more than
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| 286 | maxsplit places (resulting in at most maxsplit+1 words). If sep
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| 287 | is not specified or is None, any whitespace string is a separator.
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| 288 |
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| 289 | (split and splitfields are synonymous)
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| 290 |
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| 291 | """
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| 292 | return s.split(sep, maxsplit)
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| 293 | splitfields = split
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| 294 |
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| 295 | # Split a string into a list of space/tab-separated words
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| 296 | def rsplit(s, sep=None, maxsplit=-1):
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| 297 | """rsplit(s [,sep [,maxsplit]]) -> list of strings
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| 298 |
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| 299 | Return a list of the words in the string s, using sep as the
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| 300 | delimiter string, starting at the end of the string and working
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| 301 | to the front. If maxsplit is given, at most maxsplit splits are
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| 302 | done. If sep is not specified or is None, any whitespace string
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| 303 | is a separator.
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| 304 | """
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| 305 | return s.rsplit(sep, maxsplit)
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| 306 |
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| 307 | # Join fields with optional separator
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| 308 | def join(words, sep = ' '):
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| 309 | """join(list [,sep]) -> string
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| 310 |
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| 311 | Return a string composed of the words in list, with
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| 312 | intervening occurrences of sep. The default separator is a
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| 313 | single space.
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| 314 |
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| 315 | (joinfields and join are synonymous)
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| 316 |
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| 317 | """
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| 318 | return sep.join(words)
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| 319 | joinfields = join
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| 320 |
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| 321 | # Find substring, raise exception if not found
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| 322 | def index(s, *args):
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| 323 | """index(s, sub [,start [,end]]) -> int
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| 324 |
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| 325 | Like find but raises ValueError when the substring is not found.
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| 326 |
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| 327 | """
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| 328 | return s.index(*args)
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| 329 |
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| 330 | # Find last substring, raise exception if not found
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| 331 | def rindex(s, *args):
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| 332 | """rindex(s, sub [,start [,end]]) -> int
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| 333 |
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| 334 | Like rfind but raises ValueError when the substring is not found.
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| 335 |
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| 336 | """
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| 337 | return s.rindex(*args)
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| 338 |
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| 339 | # Count non-overlapping occurrences of substring
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| 340 | def count(s, *args):
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| 341 | """count(s, sub[, start[,end]]) -> int
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| 342 |
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| 343 | Return the number of occurrences of substring sub in string
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| 344 | s[start:end]. Optional arguments start and end are
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| 345 | interpreted as in slice notation.
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| 346 |
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| 347 | """
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| 348 | return s.count(*args)
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| 349 |
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| 350 | # Find substring, return -1 if not found
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| 351 | def find(s, *args):
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| 352 | """find(s, sub [,start [,end]]) -> in
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| 353 |
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| 354 | Return the lowest index in s where substring sub is found,
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| 355 | such that sub is contained within s[start,end]. Optional
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| 356 | arguments start and end are interpreted as in slice notation.
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| 357 |
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| 358 | Return -1 on failure.
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| 359 |
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| 360 | """
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| 361 | return s.find(*args)
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| 362 |
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| 363 | # Find last substring, return -1 if not found
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| 364 | def rfind(s, *args):
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| 365 | """rfind(s, sub [,start [,end]]) -> int
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| 366 |
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| 367 | Return the highest index in s where substring sub is found,
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| 368 | such that sub is contained within s[start,end]. Optional
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| 369 | arguments start and end are interpreted as in slice notation.
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| 370 |
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| 371 | Return -1 on failure.
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| 372 |
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| 373 | """
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| 374 | return s.rfind(*args)
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| 375 |
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| 376 | # for a bit of speed
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| 377 | _float = float
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| 378 | _int = int
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| 379 | _long = long
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| 380 |
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| 381 | # Convert string to float
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| 382 | def atof(s):
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| 383 | """atof(s) -> float
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| 384 |
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| 385 | Return the floating point number represented by the string s.
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| 386 |
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| 387 | """
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| 388 | return _float(s)
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| 389 |
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| 390 |
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| 391 | # Convert string to integer
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| 392 | def atoi(s , base=10):
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| 393 | """atoi(s [,base]) -> int
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| 394 |
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| 395 | Return the integer represented by the string s in the given
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| 396 | base, which defaults to 10. The string s must consist of one
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| 397 | or more digits, possibly preceded by a sign. If base is 0, it
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| 398 | is chosen from the leading characters of s, 0 for octal, 0x or
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| 399 | 0X for hexadecimal. If base is 16, a preceding 0x or 0X is
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| 400 | accepted.
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| 401 |
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| 402 | """
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| 403 | return _int(s, base)
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| 404 |
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| 405 |
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| 406 | # Convert string to long integer
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| 407 | def atol(s, base=10):
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| 408 | """atol(s [,base]) -> long
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| 409 |
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| 410 | Return the long integer represented by the string s in the
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| 411 | given base, which defaults to 10. The string s must consist
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| 412 | of one or more digits, possibly preceded by a sign. If base
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| 413 | is 0, it is chosen from the leading characters of s, 0 for
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| 414 | octal, 0x or 0X for hexadecimal. If base is 16, a preceding
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| 415 | 0x or 0X is accepted. A trailing L or l is not accepted,
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| 416 | unless base is 0.
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| 417 |
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| 418 | """
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| 419 | return _long(s, base)
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| 420 |
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| 421 |
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| 422 | # Left-justify a string
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| 423 | def ljust(s, width, *args):
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| 424 | """ljust(s, width[, fillchar]) -> string
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| 425 |
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| 426 | Return a left-justified version of s, in a field of the
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| 427 | specified width, padded with spaces as needed. The string is
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| 428 | never truncated. If specified the fillchar is used instead of spaces.
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| 429 |
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| 430 | """
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| 431 | return s.ljust(width, *args)
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| 432 |
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| 433 | # Right-justify a string
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| 434 | def rjust(s, width, *args):
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| 435 | """rjust(s, width[, fillchar]) -> string
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| 436 |
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| 437 | Return a right-justified version of s, in a field of the
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| 438 | specified width, padded with spaces as needed. The string is
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| 439 | never truncated. If specified the fillchar is used instead of spaces.
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| 440 |
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| 441 | """
|
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| 442 | return s.rjust(width, *args)
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| 443 |
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| 444 | # Center a string
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| 445 | def center(s, width, *args):
|
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| 446 | """center(s, width[, fillchar]) -> string
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| 447 |
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| 448 | Return a center version of s, in a field of the specified
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| 449 | width. padded with spaces as needed. The string is never
|
---|
| 450 | truncated. If specified the fillchar is used instead of spaces.
|
---|
| 451 |
|
---|
| 452 | """
|
---|
| 453 | return s.center(width, *args)
|
---|
| 454 |
|
---|
| 455 | # Zero-fill a number, e.g., (12, 3) --> '012' and (-3, 3) --> '-03'
|
---|
| 456 | # Decadent feature: the argument may be a string or a number
|
---|
| 457 | # (Use of this is deprecated; it should be a string as with ljust c.s.)
|
---|
| 458 | def zfill(x, width):
|
---|
| 459 | """zfill(x, width) -> string
|
---|
| 460 |
|
---|
| 461 | Pad a numeric string x with zeros on the left, to fill a field
|
---|
| 462 | of the specified width. The string x is never truncated.
|
---|
| 463 |
|
---|
| 464 | """
|
---|
| 465 | if not isinstance(x, basestring):
|
---|
| 466 | x = repr(x)
|
---|
| 467 | return x.zfill(width)
|
---|
| 468 |
|
---|
| 469 | # Expand tabs in a string.
|
---|
| 470 | # Doesn't take non-printing chars into account, but does understand \n.
|
---|
| 471 | def expandtabs(s, tabsize=8):
|
---|
| 472 | """expandtabs(s [,tabsize]) -> string
|
---|
| 473 |
|
---|
| 474 | Return a copy of the string s with all tab characters replaced
|
---|
| 475 | by the appropriate number of spaces, depending on the current
|
---|
| 476 | column, and the tabsize (default 8).
|
---|
| 477 |
|
---|
| 478 | """
|
---|
| 479 | return s.expandtabs(tabsize)
|
---|
| 480 |
|
---|
| 481 | # Character translation through look-up table.
|
---|
| 482 | def translate(s, table, deletions=""):
|
---|
| 483 | """translate(s,table [,deletions]) -> string
|
---|
| 484 |
|
---|
| 485 | Return a copy of the string s, where all characters occurring
|
---|
| 486 | in the optional argument deletions are removed, and the
|
---|
| 487 | remaining characters have been mapped through the given
|
---|
| 488 | translation table, which must be a string of length 256. The
|
---|
| 489 | deletions argument is not allowed for Unicode strings.
|
---|
| 490 |
|
---|
| 491 | """
|
---|
| 492 | if deletions or table is None:
|
---|
| 493 | return s.translate(table, deletions)
|
---|
| 494 | else:
|
---|
| 495 | # Add s[:0] so that if s is Unicode and table is an 8-bit string,
|
---|
| 496 | # table is converted to Unicode. This means that table *cannot*
|
---|
| 497 | # be a dictionary -- for that feature, use u.translate() directly.
|
---|
| 498 | return s.translate(table + s[:0])
|
---|
| 499 |
|
---|
| 500 | # Capitalize a string, e.g. "aBc dEf" -> "Abc def".
|
---|
| 501 | def capitalize(s):
|
---|
| 502 | """capitalize(s) -> string
|
---|
| 503 |
|
---|
| 504 | Return a copy of the string s with only its first character
|
---|
| 505 | capitalized.
|
---|
| 506 |
|
---|
| 507 | """
|
---|
| 508 | return s.capitalize()
|
---|
| 509 |
|
---|
| 510 | # Substring replacement (global)
|
---|
[391] | 511 | def replace(s, old, new, maxreplace=-1):
|
---|
| 512 | """replace (str, old, new[, maxreplace]) -> string
|
---|
[2] | 513 |
|
---|
| 514 | Return a copy of string str with all occurrences of substring
|
---|
[391] | 515 | old replaced by new. If the optional argument maxreplace is
|
---|
| 516 | given, only the first maxreplace occurrences are replaced.
|
---|
[2] | 517 |
|
---|
| 518 | """
|
---|
[391] | 519 | return s.replace(old, new, maxreplace)
|
---|
[2] | 520 |
|
---|
| 521 |
|
---|
| 522 | # Try importing optional built-in module "strop" -- if it exists,
|
---|
| 523 | # it redefines some string operations that are 100-1000 times faster.
|
---|
| 524 | # It also defines values for whitespace, lowercase and uppercase
|
---|
| 525 | # that match <ctype.h>'s definitions.
|
---|
| 526 |
|
---|
| 527 | try:
|
---|
| 528 | from strop import maketrans, lowercase, uppercase, whitespace
|
---|
| 529 | letters = lowercase + uppercase
|
---|
| 530 | except ImportError:
|
---|
| 531 | pass # Use the original versions
|
---|
| 532 |
|
---|
| 533 | ########################################################################
|
---|
| 534 | # the Formatter class
|
---|
| 535 | # see PEP 3101 for details and purpose of this class
|
---|
| 536 |
|
---|
| 537 | # The hard parts are reused from the C implementation. They're exposed as "_"
|
---|
| 538 | # prefixed methods of str and unicode.
|
---|
| 539 |
|
---|
| 540 | # The overall parser is implemented in str._formatter_parser.
|
---|
| 541 | # The field name parser is implemented in str._formatter_field_name_split
|
---|
| 542 |
|
---|
| 543 | class Formatter(object):
|
---|
| 544 | def format(self, format_string, *args, **kwargs):
|
---|
| 545 | return self.vformat(format_string, args, kwargs)
|
---|
| 546 |
|
---|
| 547 | def vformat(self, format_string, args, kwargs):
|
---|
| 548 | used_args = set()
|
---|
| 549 | result = self._vformat(format_string, args, kwargs, used_args, 2)
|
---|
| 550 | self.check_unused_args(used_args, args, kwargs)
|
---|
| 551 | return result
|
---|
| 552 |
|
---|
| 553 | def _vformat(self, format_string, args, kwargs, used_args, recursion_depth):
|
---|
| 554 | if recursion_depth < 0:
|
---|
| 555 | raise ValueError('Max string recursion exceeded')
|
---|
| 556 | result = []
|
---|
| 557 | for literal_text, field_name, format_spec, conversion in \
|
---|
| 558 | self.parse(format_string):
|
---|
| 559 |
|
---|
| 560 | # output the literal text
|
---|
| 561 | if literal_text:
|
---|
| 562 | result.append(literal_text)
|
---|
| 563 |
|
---|
| 564 | # if there's a field, output it
|
---|
| 565 | if field_name is not None:
|
---|
| 566 | # this is some markup, find the object and do
|
---|
| 567 | # the formatting
|
---|
| 568 |
|
---|
| 569 | # given the field_name, find the object it references
|
---|
| 570 | # and the argument it came from
|
---|
| 571 | obj, arg_used = self.get_field(field_name, args, kwargs)
|
---|
| 572 | used_args.add(arg_used)
|
---|
| 573 |
|
---|
| 574 | # do any conversion on the resulting object
|
---|
| 575 | obj = self.convert_field(obj, conversion)
|
---|
| 576 |
|
---|
| 577 | # expand the format spec, if needed
|
---|
| 578 | format_spec = self._vformat(format_spec, args, kwargs,
|
---|
| 579 | used_args, recursion_depth-1)
|
---|
| 580 |
|
---|
| 581 | # format the object and append to the result
|
---|
| 582 | result.append(self.format_field(obj, format_spec))
|
---|
| 583 |
|
---|
| 584 | return ''.join(result)
|
---|
| 585 |
|
---|
| 586 |
|
---|
| 587 | def get_value(self, key, args, kwargs):
|
---|
| 588 | if isinstance(key, (int, long)):
|
---|
| 589 | return args[key]
|
---|
| 590 | else:
|
---|
| 591 | return kwargs[key]
|
---|
| 592 |
|
---|
| 593 |
|
---|
| 594 | def check_unused_args(self, used_args, args, kwargs):
|
---|
| 595 | pass
|
---|
| 596 |
|
---|
| 597 |
|
---|
| 598 | def format_field(self, value, format_spec):
|
---|
| 599 | return format(value, format_spec)
|
---|
| 600 |
|
---|
| 601 |
|
---|
| 602 | def convert_field(self, value, conversion):
|
---|
| 603 | # do any conversion on the resulting object
|
---|
[391] | 604 | if conversion is None:
|
---|
| 605 | return value
|
---|
[2] | 606 | elif conversion == 's':
|
---|
| 607 | return str(value)
|
---|
[391] | 608 | elif conversion == 'r':
|
---|
| 609 | return repr(value)
|
---|
| 610 | raise ValueError("Unknown conversion specifier {0!s}".format(conversion))
|
---|
[2] | 611 |
|
---|
| 612 |
|
---|
| 613 | # returns an iterable that contains tuples of the form:
|
---|
| 614 | # (literal_text, field_name, format_spec, conversion)
|
---|
| 615 | # literal_text can be zero length
|
---|
| 616 | # field_name can be None, in which case there's no
|
---|
| 617 | # object to format and output
|
---|
| 618 | # if field_name is not None, it is looked up, formatted
|
---|
| 619 | # with format_spec and conversion and then used
|
---|
| 620 | def parse(self, format_string):
|
---|
| 621 | return format_string._formatter_parser()
|
---|
| 622 |
|
---|
| 623 |
|
---|
| 624 | # given a field_name, find the object it references.
|
---|
| 625 | # field_name: the field being looked up, e.g. "0.name"
|
---|
| 626 | # or "lookup[3]"
|
---|
| 627 | # used_args: a set of which args have been used
|
---|
| 628 | # args, kwargs: as passed in to vformat
|
---|
| 629 | def get_field(self, field_name, args, kwargs):
|
---|
| 630 | first, rest = field_name._formatter_field_name_split()
|
---|
| 631 |
|
---|
| 632 | obj = self.get_value(first, args, kwargs)
|
---|
| 633 |
|
---|
| 634 | # loop through the rest of the field_name, doing
|
---|
| 635 | # getattr or getitem as needed
|
---|
| 636 | for is_attr, i in rest:
|
---|
| 637 | if is_attr:
|
---|
| 638 | obj = getattr(obj, i)
|
---|
| 639 | else:
|
---|
| 640 | obj = obj[i]
|
---|
| 641 |
|
---|
| 642 | return obj, first
|
---|