"""A collection of string operations (most are no longer used).

Warning: most of the code you see here isn't normally used nowadays.

Beginning with Python 1.6, many of these functions are implemented as

methods on the standard string object. They used to be implemented by

a built-in module called strop, but strop is now obsolete itself.

Public module variables:

whitespace -- a string containing all characters considered whitespace

lowercase -- a string containing all characters considered lowercase letters

uppercase -- a string containing all characters considered uppercase letters

letters -- a string containing all characters considered letters

digits -- a string containing all characters considered decimal digits

hexdigits -- a string containing all characters considered hexadecimal digits

octdigits -- a string containing all characters considered octal digits

punctuation -- a string containing all characters considered punctuation

printable -- a string containing all characters considered printable

"""

# Some strings for ctype-style character classification

whitespace = ' \t\n\r\v\f'

lowercase = 'abcdefghijklmnopqrstuvwxyz'

uppercase = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

letters = lowercase + uppercase

ascii_lowercase = lowercase

ascii_uppercase = uppercase

ascii_letters = ascii_lowercase + ascii_uppercase

digits = '0123456789'

hexdigits = digits + 'abcdef' + 'ABCDEF'

octdigits = '01234567'

punctuation = """!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"""

printable = digits + letters + punctuation + whitespace

# Case conversion helpers

# Use str to convert Unicode literal in case of -U

l = map(chr, xrange(256))

_idmap = str('').join(l)

del l

# Functions which aren't available as string methods.

# Capitalize the words in a string, e.g. " aBc  dEf " -> "Abc Def".

def capwords(s, sep=None):

    """capwords(s, [sep]) -> string

    Split the argument into words using split, capitalize each

    word using capitalize, and join the capitalized words using

    join. Note that this replaces runs of whitespace characters by

    a single space.

    """

    return (sep or ' ').join([x.capitalize() for x in s.split(sep)])

# Construct a translation string

_idmapL = None

def maketrans(fromstr, tostr):

    """maketrans(frm, to) -> string

    Return a translation table (a string of 256 bytes long)

    suitable for use in string.translate.  The strings frm and to

    must be of the same length.

    """

    if len(fromstr) != len(tostr):

        raise ValueError, "maketrans arguments must have same length"

    global _idmapL

    if not _idmapL:

        _idmapL = list(_idmap)

    L = _idmapL[:]

    fromstr = map(ord, fromstr)

    for i in range(len(fromstr)):

        L[fromstr[i]] = tostr[i]

    return ''.join(L)

####################################################################

import re as _re

class _multimap:

    """Helper class for combining multiple mappings.

    Used by .{safe_,}substitute() to combine the mapping and keyword

    arguments.

    """

    def __init__(self, primary, secondary):

        self._primary = primary

        self._secondary = secondary

    def __getitem__(self, key):

        try:

            return self._primary[key]

        except KeyError:

            return self._secondary[key]

class _TemplateMetaclass(type):

    pattern = r"""

    %(delim)s(?:

      (?P<escaped>%(delim)s) |   # Escape sequence of two delimiters

      (?P<named>%(id)s)      |   # delimiter and a Python identifier

      {(?P<braced>%(id)s)}   |   # delimiter and a braced identifier

      (?P<invalid>)              # Other ill-formed delimiter exprs

    )

    """

    def __init__(cls, name, bases, dct):

        super(_TemplateMetaclass, cls).__init__(name, bases, dct)

        if 'pattern' in dct:

            pattern = cls.pattern

        else:

            pattern = _TemplateMetaclass.pattern % {

                'delim' : _re.escape(cls.delimiter),

                'id'    : cls.idpattern,

                }

        cls.pattern = _re.compile(pattern, _re.IGNORECASE | _re.VERBOSE)

class Template:

    """A string class for supporting $-substitutions."""

    __metaclass__ = _TemplateMetaclass

    delimiter = '$'

    idpattern = r'[_a-z][_a-z0-9]*'

    def __init__(self, template):

        self.template = template

    # Search for $$, $identifier, ${identifier}, and any bare $'s

    def _invalid(self, mo):

        i = mo.start('invalid')

        lines = self.template[:i].splitlines(True)

        if not lines:

            colno = 1

            lineno = 1

        else:

            colno = i - len(''.join(lines[:-1]))

            lineno = len(lines)

        raise ValueError('Invalid placeholder in string: line %d, col %d' %

                         (lineno, colno))

    def substitute(self, *args, **kws):

        if len(args) > 1:

            raise TypeError('Too many positional arguments')

        if not args:

            mapping = kws

        elif kws:

            mapping = _multimap(kws, args[0])

        else:

            mapping = args[0]

        # Helper function for .sub()

        def convert(mo):

            # Check the most common path first.

            named = mo.group('named') or mo.group('braced')

            if named is not None:

                val = mapping[named]

                # We use this idiom instead of str() because the latter will

                # fail if val is a Unicode containing non-ASCII characters.

                return '%s' % (val,)

            if mo.group('escaped') is not None:

                return self.delimiter

            if mo.group('invalid') is not None:

                self._invalid(mo)

            raise ValueError('Unrecognized named group in pattern',

                             self.pattern)

        return self.pattern.sub(convert, self.template)

    def safe_substitute(self, *args, **kws):

        if len(args) > 1:

            raise TypeError('Too many positional arguments')

        if not args:

            mapping = kws

        elif kws:

            mapping = _multimap(kws, args[0])

        else:

            mapping = args[0]

        # Helper function for .sub()

        def convert(mo):

            named = mo.group('named')

            if named is not None:

                try:

                    # We use this idiom instead of str() because the latter

                    # will fail if val is a Unicode containing non-ASCII

                    return '%s' % (mapping[named],)

                except KeyError:

                    return self.delimiter + named

            braced = mo.group('braced')

            if braced is not None:

                try:

                    return '%s' % (mapping[braced],)

                except KeyError:

                    return self.delimiter + '{' + braced + '}'

            if mo.group('escaped') is not None:

                return self.delimiter

            if mo.group('invalid') is not None:

                return self.delimiter

            raise ValueError('Unrecognized named group in pattern',

                             self.pattern)

        return self.pattern.sub(convert, self.template)

####################################################################

# NOTE: Everything below here is deprecated.  Use string methods instead.

# This stuff will go away in Python 3.0.

# Backward compatible names for exceptions

index_error = ValueError

atoi_error = ValueError

atof_error = ValueError

atol_error = ValueError

# convert UPPER CASE letters to lower case

def lower(s):

    """lower(s) -> string

    Return a copy of the string s converted to lowercase.

    """

    return s.lower()

# Convert lower case letters to UPPER CASE

def upper(s):

    """upper(s) -> string

    Return a copy of the string s converted to uppercase.

    """

    return s.upper()

# Swap lower case letters and UPPER CASE

def swapcase(s):

    """swapcase(s) -> string

    Return a copy of the string s with upper case characters

    converted to lowercase and vice versa.

    """

    return s.swapcase()

# Strip leading and trailing tabs and spaces

def strip(s, chars=None):

    """strip(s [,chars]) -> string

    Return a copy of the string s with leading and trailing

    whitespace removed.

    If chars is given and not None, remove characters in chars instead.

    If chars is unicode, S will be converted to unicode before stripping.

    """

    return s.strip(chars)

# Strip leading tabs and spaces

def lstrip(s, chars=None):

    """lstrip(s [,chars]) -> string

    Return a copy of the string s with leading whitespace removed.

    If chars is given and not None, remove characters in chars instead.

    """

    return s.lstrip(chars)

# Strip trailing tabs and spaces

def rstrip(s, chars=None):

    """rstrip(s [,chars]) -> string

    Return a copy of the string s with trailing whitespace removed.

    If chars is given and not None, remove characters in chars instead.

    """

    return s.rstrip(chars)

# Split a string into a list of space/tab-separated words

def split(s, sep=None, maxsplit=-1):

    """split(s [,sep [,maxsplit]]) -> list of strings

    Return a list of the words in the string s, using sep as the

    delimiter string.  If maxsplit is given, splits at no more than

    maxsplit places (resulting in at most maxsplit+1 words).  If sep

    is not specified or is None, any whitespace string is a separator.

    (split and splitfields are synonymous)

    """

    return s.split(sep, maxsplit)

splitfields = split

# Split a string into a list of space/tab-separated words

def rsplit(s, sep=None, maxsplit=-1):

    """rsplit(s [,sep [,maxsplit]]) -> list of strings

    Return a list of the words in the string s, using sep as the

    delimiter string, starting at the end of the string and working

    to the front.  If maxsplit is given, at most maxsplit splits are

    done. If sep is not specified or is None, any whitespace string

    is a separator.

    """

    return s.rsplit(sep, maxsplit)

# Join fields with optional separator

def join(words, sep = ' '):

    """join(list [,sep]) -> string

    Return a string composed of the words in list, with

    intervening occurrences of sep.  The default separator is a

    single space.

    (joinfields and join are synonymous)

    """

    return sep.join(words)

joinfields = join

# Find substring, raise exception if not found

def index(s, *args):

    """index(s, sub [,start [,end]]) -> int

    Like find but raises ValueError when the substring is not found.

    """

    return s.index(*args)

# Find last substring, raise exception if not found

def rindex(s, *args):

    """rindex(s, sub [,start [,end]]) -> int

    Like rfind but raises ValueError when the substring is not found.

    """

    return s.rindex(*args)

# Count non-overlapping occurrences of substring

def count(s, *args):

    """count(s, sub[, start[,end]]) -> int

    Return the number of occurrences of substring sub in string

    s[start:end].  Optional arguments start and end are

    interpreted as in slice notation.

    """

    return s.count(*args)

# Find substring, return -1 if not found

def find(s, *args):

    """find(s, sub [,start [,end]]) -> in

    Return the lowest index in s where substring sub is found,

    such that sub is contained within s[start,end].  Optional

    arguments start and end are interpreted as in slice notation.

    Return -1 on failure.

    """

    return s.find(*args)

# Find last substring, return -1 if not found

def rfind(s, *args):

    """rfind(s, sub [,start [,end]]) -> int

    Return the highest index in s where substring sub is found,

    such that sub is contained within s[start,end].  Optional

    arguments start and end are interpreted as in slice notation.

    Return -1 on failure.

    """

    return s.rfind(*args)

# for a bit of speed

_float = float

_int = int

_long = long

# Convert string to float

def atof(s):

    """atof(s) -> float

    Return the floating point number represented by the string s.

    """

    return _float(s)

# Convert string to integer

def atoi(s , base=10):

    """atoi(s [,base]) -> int

    Return the integer represented by the string s in the given

    base, which defaults to 10.  The string s must consist of one

    or more digits, possibly preceded by a sign.  If base is 0, it

    is chosen from the leading characters of s, 0 for octal, 0x or

    0X for hexadecimal.  If base is 16, a preceding 0x or 0X is

    accepted.

    """

    return _int(s, base)

# Convert string to long integer

def atol(s, base=10):

    """atol(s [,base]) -> long

    Return the long integer represented by the string s in the

    given base, which defaults to 10.  The string s must consist

    of one or more digits, possibly preceded by a sign.  If base

    is 0, it is chosen from the leading characters of s, 0 for

    octal, 0x or 0X for hexadecimal.  If base is 16, a preceding

    0x or 0X is accepted.  A trailing L or l is not accepted,

    unless base is 0.

    """

    return _long(s, base)

# Left-justify a string

def ljust(s, width, *args):

    """ljust(s, width[, fillchar]) -> string

    Return a left-justified version of s, in a field of the

    specified width, padded with spaces as needed.  The string is

    never truncated.  If specified the fillchar is used instead of spaces.

    """

    return s.ljust(width, *args)

# Right-justify a string

def rjust(s, width, *args):

    """rjust(s, width[, fillchar]) -> string

    Return a right-justified version of s, in a field of the

    specified width, padded with spaces as needed.  The string is

    never truncated.  If specified the fillchar is used instead of spaces.

    """

    return s.rjust(width, *args)

# Center a string

def center(s, width, *args):

    """center(s, width[, fillchar]) -> string

    Return a center version of s, in a field of the specified

    width. padded with spaces as needed.  The string is never

    truncated.  If specified the fillchar is used instead of spaces.

    """

    return s.center(width, *args)

# Zero-fill a number, e.g., (12, 3) --> '012' and (-3, 3) --> '-03'

# Decadent feature: the argument may be a string or a number

# (Use of this is deprecated; it should be a string as with ljust c.s.)

def zfill(x, width):

    """zfill(x, width) -> string

    Pad a numeric string x with zeros on the left, to fill a field

    of the specified width.  The string x is never truncated.

    """

    if not isinstance(x, basestring):

        x = repr(x)

    return x.zfill(width)

# Expand tabs in a string.

# Doesn't take non-printing chars into account, but does understand \n.

def expandtabs(s, tabsize=8):

    """expandtabs(s [,tabsize]) -> string

    Return a copy of the string s with all tab characters replaced

    by the appropriate number of spaces, depending on the current

    column, and the tabsize (default 8).

    """

    return s.expandtabs(tabsize)

# Character translation through look-up table.

def translate(s, table, deletions=""):

    """translate(s,table [,deletions]) -> string

    Return a copy of the string s, where all characters occurring

    in the optional argument deletions are removed, and the

    remaining characters have been mapped through the given

    translation table, which must be a string of length 256.  The

    deletions argument is not allowed for Unicode strings.

    """

    if deletions or table is None:

        return s.translate(table, deletions)

    else:

        # Add s[:0] so that if s is Unicode and table is an 8-bit string,

        # table is converted to Unicode.  This means that table *cannot*

        # be a dictionary -- for that feature, use u.translate() directly.

        return s.translate(table + s[:0])

# Capitalize a string, e.g. "aBc  dEf" -> "Abc  def".

def capitalize(s):

    """capitalize(s) -> string

    Return a copy of the string s with only its first character

    capitalized.

    """

    return s.capitalize()

# Substring replacement (global)

def replace(s, old, new, maxsplit=-1):

    """replace (str, old, new[, maxsplit]) -> string

    Return a copy of string str with all occurrences of substring

    old replaced by new. If the optional argument maxsplit is

    given, only the first maxsplit occurrences are replaced.

    """

    return s.replace(old, new, maxsplit)

# Try importing optional built-in module "strop" -- if it exists,

# it redefines some string operations that are 100-1000 times faster.

# It also defines values for whitespace, lowercase and uppercase

# that match <ctype.h>'s definitions.

try:

    from strop import maketrans, lowercase, uppercase, whitespace

    letters = lowercase + uppercase

except ImportError: