Mainlining the string_methods branch. See branch revision log

messages for specific changes.

1 files changed, 275 insertions, 430 deletions

diff --git a/Lib/string.py b/Lib/string.py
index e449c20765..2c3083e221 100644
--- a/Lib/string.py
+++ b/Lib/string.py
@@ -1,8 +1,9 @@
 # module 'string' -- A collection of string operations
 
-# Warning: most of the code you see here isn't normally used nowadays.
-# At the end of this file most functions are replaced by built-in
-# functions imported from built-in module "strop".
+# Warning: most of the code you see here isn't normally used nowadays.  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.
 
 """Common string manipulations.
 
@@ -30,9 +31,6 @@ octdigits = '01234567'
 # Case conversion helpers
 _idmap = ''
 for i in range(256): _idmap = _idmap + chr(i)
-_lower = _idmap[:ord('A')] + lowercase + _idmap[ord('Z')+1:]
-_upper = _idmap[:ord('a')] + uppercase + _idmap[ord('z')+1:]
-_swapcase = _upper[:ord('A')] + lowercase + _upper[ord('Z')+1:]
 del i
 
 # Backward compatible names for exceptions
@@ -43,544 +41,391 @@ atol_error = ValueError
 
 # convert UPPER CASE letters to lower case
 def lower(s):
-	"""lower(s) -> string
+    """lower(s) -> string
 
-	Return a copy of the string s converted to lowercase.
+    Return a copy of the string s converted to lowercase.
 
-	"""
-	res = ''
-	for c in s:
-		res = res + _lower[ord(c)]
-	return res
+    """
+    return s.lower()
 
 # Convert lower case letters to UPPER CASE
 def upper(s):
-	"""upper(s) -> string
+    """upper(s) -> string
 
-	Return a copy of the string s converted to uppercase.
+    Return a copy of the string s converted to uppercase.
 
-	"""
-	res = ''
-	for c in s:
-		res = res + _upper[ord(c)]
-	return res
+    """
+    return s.upper()
 
 # Swap lower case letters and UPPER CASE
 def swapcase(s):
-	"""swapcase(s) -> string
+    """swapcase(s) -> string
 
-	Return a copy of the string s with upper case characters
-	converted to lowercase and vice versa.
+    Return a copy of the string s with upper case characters
+    converted to lowercase and vice versa.
 
-	"""
-	res = ''
-	for c in s:
-		res = res + _swapcase[ord(c)]
-	return res
+    """
+    return s.swapcase()
 
 # Strip leading and trailing tabs and spaces
 def strip(s):
-	"""strip(s) -> string
+    """strip(s) -> string
 
-	Return a copy of the string s with leading and trailing
-	whitespace removed.
+    Return a copy of the string s with leading and trailing
+    whitespace removed.
 
-	"""
-	i, j = 0, len(s)
-	while i < j and s[i] in whitespace: i = i+1
-	while i < j and s[j-1] in whitespace: j = j-1
-	return s[i:j]
+    """
+    return s.strip()
 
 # Strip leading tabs and spaces
 def lstrip(s):
-	"""lstrip(s) -> string
+    """lstrip(s) -> string
 
-	Return a copy of the string s with leading whitespace removed.
+    Return a copy of the string s with leading whitespace removed.
 
-	"""
-	i, j = 0, len(s)
-	while i < j and s[i] in whitespace: i = i+1
-	return s[i:j]
+    """
+    return s.lstrip()
 
 # Strip trailing tabs and spaces
 def rstrip(s):
-	"""rstrip(s) -> string
+    """rstrip(s) -> string
 
-	Return a copy of the string s with trailing whitespace
-	removed.
+    Return a copy of the string s with trailing whitespace
+    removed.
 
-	"""
-	i, j = 0, len(s)
-	while i < j and s[j-1] in whitespace: j = j-1
-	return s[i:j]
+    """
+    return s.rstrip()
 
 
 # Split a string into a list of space/tab-separated words
 # NB: split(s) is NOT the same as splitfields(s, ' ')!
 def split(s, sep=None, maxsplit=0):
-	"""split(str [,sep [,maxsplit]]) -> list of strings
-
-	Return a list of the words in the string s, using sep as the
-	delimiter string.  If maxsplit is nonzero, splits into at most
-	maxsplit words If sep is not specified, any whitespace string
-	is a separator.  Maxsplit defaults to 0.
-
-	(split and splitfields are synonymous)
-
-	"""
-	if sep is not None: return splitfields(s, sep, maxsplit)
-	res = []
-	i, n = 0, len(s)
-	if maxsplit <= 0: maxsplit = n
-	count = 0
-	while i < n:
-		while i < n and s[i] in whitespace: i = i+1
-		if i == n: break
-		if count >= maxsplit:
-		    res.append(s[i:])
-		    break
-		j = i
-		while j < n and s[j] not in whitespace: j = j+1
-		count = count + 1
-		res.append(s[i:j])
-		i = j
-	return res
-
-# Split a list into fields separated by a given string
-# NB: splitfields(s, ' ') is NOT the same as split(s)!
-# splitfields(s, '') returns [s] (in analogy with split() in nawk)
-def splitfields(s, sep=None, maxsplit=0):
-	"""splitfields(str [,sep [,maxsplit]]) -> list of strings
-
-	Return a list of the words in the string s, using sep as the
-	delimiter string.  If maxsplit is nonzero, splits into at most
-	maxsplit words If sep is not specified, any whitespace string
-	is a separator.  Maxsplit defaults to 0.
-
-	(split and splitfields are synonymous)
-
-	"""
-	if sep is None: return split(s, None, maxsplit)
-	res = []
-	nsep = len(sep)
-	if nsep == 0:
-		return [s]
-	ns = len(s)
-	if maxsplit <= 0: maxsplit = ns
-	i = j = 0
-	count = 0
-	while j+nsep <= ns:
-		if s[j:j+nsep] == sep:
-			count = count + 1
-			res.append(s[i:j])
-			i = j = j + nsep
-			if count >= maxsplit: break
-		else:
-			j = j + 1
-	res.append(s[i:])
-	return res
-
-# Join words with spaces between them
-def join(words, sep = ' '):
-	"""join(list [,sep]) -> string
+    """split(str [,sep [,maxsplit]]) -> list of strings
 
-	Return a string composed of the words in list, with
-	intervening occurences of sep.  Sep defaults to a single
-	space.
+    Return a list of the words in the string s, using sep as the
+    delimiter string.  If maxsplit is nonzero, splits into at most
+    maxsplit words If sep is not specified, any whitespace string
+    is a separator.  Maxsplit defaults to 0.
 
-	(joinfields and join are synonymous)
+    (split and splitfields are synonymous)
 
-	"""
-	return joinfields(words, sep)
+    """
+    return s.split(sep, maxsplit)
+splitfields = split
 
 # Join fields with optional separator
-def joinfields(words, sep = ' '):
-	"""joinfields(list [,sep]) -> string
+def join(words, sep = ' '):
+    """join(list [,sep]) -> string
 
-	Return a string composed of the words in list, with
-	intervening occurences of sep.  The default separator is a
-	single space.
+    Return a string composed of the words in list, with
+    intervening occurences of sep.  The default separator is a
+    single space.
 
-	(joinfields and join are synonymous)
+    (joinfields and join are synonymous)
 
-	"""
-	res = ''
-	for w in words:
-		res = res + (sep + w)
-	return res[len(sep):]
+    """
+    return sep.join(words)
+joinfields = join
 
-# Find substring, raise exception if not found
-def index(s, sub, i = 0, last=None):
-	"""index(s, sub [,start [,end]]) -> int
+# for a little bit of speed
+_apply = apply
 
-	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.
+# Find substring, raise exception if not found
+def index(s, *args):
+    """index(s, sub [,start [,end]]) -> int
 
-	Raise ValueError if not found.
+    Like find but raises ValueError when the substring is not found.
 
-	"""
-	if last is None: last = len(s)
-	res = find(s, sub, i, last)
-	if res < 0:
-		raise ValueError, 'substring not found in string.index'
-	return res
+    """
+    return _apply(s.index, args)
 
 # Find last substring, raise exception if not found
-def rindex(s, sub, i = 0, last=None):
-	"""rindex(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.
+def rindex(s, *args):
+    """rindex(s, sub [,start [,end]]) -> int
 
-	Raise ValueError if not found.
+    Like rfind but raises ValueError when the substring is not found.
 
-	"""
-	if last is None: last = len(s)
-	res = rfind(s, sub, i, last)
-	if res < 0:
-		raise ValueError, 'substring not found in string.index'
-	return res
+    """
+    return _apply(s.rindex, args)
 
 # Count non-overlapping occurrences of substring
-def count(s, sub, i = 0, last=None):
-	"""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.
-
-	"""
-	Slen = len(s)  # cache this value, for speed
-	if last is None:
-		last = Slen
-	elif last < 0:
-		last = max(0, last + Slen)
-	elif last > Slen:
-		last = Slen
-	if i < 0: i = max(0, i + Slen)
-	n = len(sub)
-	m = last + 1 - n
-	if n == 0: return m-i
-	r = 0
-	while i < m:
-		if sub == s[i:i+n]:
-			r = r+1
-			i = i+n
-		else:
-			i = i+1
-	return r
+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 _apply(s.count, args)
 
 # Find substring, return -1 if not found
-def find(s, sub, i = 0, last=None):
-	"""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.
-
-	"""
-	Slen = len(s)  # cache this value, for speed
-	if last is None:
-		last = Slen
-	elif last < 0:
-		last = max(0, last + Slen)
-	elif last > Slen:
-		last = Slen
-	if i < 0: i = max(0, i + Slen)
-	n = len(sub)
-	m = last + 1 - n
-	while i < m:
-		if sub == s[i:i+n]: return i
-		i = i+1
-	return -1
+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 _apply(s.find, args)
 
 # Find last substring, return -1 if not found
-def rfind(s, sub, i = 0, last=None):
-	"""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.
-
-	"""
-	Slen = len(s)  # cache this value, for speed
-	if last is None:
-		last = Slen
-	elif last < 0:
-		last = max(0, last + Slen)
-	elif last > Slen:
-		last = Slen
-	if i < 0: i = max(0, i + Slen)
-	n = len(sub)
-	m = last + 1 - n
-	r = -1
-	while i < m:
-		if sub == s[i:i+n]: r = i
-		i = i+1
-	return r
-
-# "Safe" environment for eval()
-_safe_env = {"__builtins__": {}}
+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 _apply(s.rfind, args)
+
+# for a bit of speed
+_float = float
+_int = int
+_long = long
+_StringType = type('')
 
 # Convert string to float
-_re = None
-def atof(str):
-	"""atof(s) -> float
-
-	Return the floating point number represented by the string s.
-
-	"""
-	global _re
-	if _re is None:
-		# Don't fail if re doesn't exist -- just skip the syntax check
-		try:
-			import re
-		except ImportError:
-			_re = 0
-		else:
-			_re = re
-	sign = ''
-	s = strip(str)
-	if s and s[0] in '+-':
-		sign = s[0]
-		s = s[1:]
-	if not s:
-		raise ValueError, 'non-float argument to string.atof'
-	while s[0] == '0' and len(s) > 1 and s[1] in digits: s = s[1:]
-	if _re and not _re.match('[0-9]*(\.[0-9]*)?([eE][-+]?[0-9]+)?$', s):
-		raise ValueError, 'non-float argument to string.atof'
-	try:
-		return float(eval(sign + s, _safe_env))
-	except SyntaxError:
-		raise ValueError, 'non-float argument to string.atof'
+def atof(s):
+    """atof(s) -> float
+
+    Return the floating point number represented by the string s.
+
+    """
+    if type(s) == _StringType:
+	return _float(s)
+    else:
+	raise TypeError('argument 1: expected string, %s found' %
+			type(s).__name__)
 
 # Convert string to integer
-def atoi(str, 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.
-
-	"""
-	if base != 10:
-		# We only get here if strop doesn't define atoi()
-		raise ValueError, "this string.atoi doesn't support base != 10"
-	sign = ''
-	s = strip(str)
-	if s and s[0] in '+-':
-		sign = s[0]
-		s = s[1:]
-	if not s:
-		raise ValueError, 'non-integer argument to string.atoi'
-	while s[0] == '0' and len(s) > 1: s = s[1:]
-	for c in s:
-		if c not in digits:
-			raise ValueError, 'non-integer argument to string.atoi'
-	return eval(sign + s, _safe_env)
+def atoi(*args):
+    """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.
+
+    """
+    try:
+	s = args[0]
+    except IndexError:
+	raise TypeError('function requires at least 1 argument: %d given' %
+			len(args))
+    # Don't catch type error resulting from too many arguments to int().  The
+    # error message isn't compatible but the error type is, and this function
+    # is complicated enough already.
+    if type(s) == _StringType:
+	return _apply(_int, args)
+    else:
+	raise TypeError('argument 1: expected string, %s found' %
+			type(s).__name__)
+
 
 # Convert string to long integer
-def atol(str, 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.
-
-	"""
-	if base != 10:
-		# We only get here if strop doesn't define atol()
-		raise ValueError, "this string.atol doesn't support base != 10"
-	sign = ''
-	s = strip(str)
-	if s and s[0] in '+-':
-		sign = s[0]
-		s = s[1:]
-	if not s:
-		raise ValueError, 'non-integer argument to string.atol'
-	while s[0] == '0' and len(s) > 1: s = s[1:]
-	for c in s:
-		if c not in digits:
-			raise ValueError, 'non-integer argument to string.atol'
-	return eval(sign + s + 'L', _safe_env)
+def atol(*args):
+    """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.
+
+    """
+    try:
+	s = args[0]
+    except IndexError:
+	raise TypeError('function requires at least 1 argument: %d given' %
+			len(args))
+    # Don't catch type error resulting from too many arguments to long().  The
+    # error message isn't compatible but the error type is, and this function
+    # is complicated enough already.
+    if type(s) == _StringType:
+	return _apply(_long, args)
+    else:
+	raise TypeError('argument 1: expected string, %s found' %
+			type(s).__name__)
+
 
 # Left-justify a string
 def ljust(s, width):
-	"""ljust(s, width) -> string
+    """ljust(s, width) -> 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.
+    Return a left-justified version of s, in a field of the
+    specified width, padded with spaces as needed.  The string is
+    never truncated.
 
-	"""
-	n = width - len(s)
-	if n <= 0: return s
-	return s + ' '*n
+    """
+    n = width - len(s)
+    if n <= 0: return s
+    return s + ' '*n
 
 # Right-justify a string
 def rjust(s, width):
-	"""rjust(s, width) -> string
+    """rjust(s, width) -> 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.
+    Return a right-justified version of s, in a field of the
+    specified width, padded with spaces as needed.  The string is
+    never truncated.
 
-	"""
-	n = width - len(s)
-	if n <= 0: return s
-	return ' '*n + s
+    """
+    n = width - len(s)
+    if n <= 0: return s
+    return ' '*n + s
 
 # Center a string
 def center(s, width):
-	"""center(s, width) -> string
+    """center(s, width) -> string
 
-	Return a center version of s, in a field of the specified
-	width. padded with spaces as needed.  The string is never
-	truncated.
+    Return a center version of s, in a field of the specified
+    width. padded with spaces as needed.  The string is never
+    truncated.
 
-	"""
-	n = width - len(s)
-	if n <= 0: return s
-	half = n/2
-	if n%2 and width%2:
-		# This ensures that center(center(s, i), j) = center(s, j)
-		half = half+1
-	return ' '*half +  s + ' '*(n-half)
+    """
+    n = width - len(s)
+    if n <= 0: return s
+    half = n/2
+    if n%2 and width%2:
+	# This ensures that center(center(s, i), j) = center(s, j)
+	half = half+1
+    return ' '*half +  s + ' '*(n-half)
 
 # 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
+    """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.
+    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 type(x) == type(''): s = x
-	else: s = `x`
-	n = len(s)
-	if n >= width: return s
-	sign = ''
-	if s[:1] in ('-', '+'):
-		sign, s = s[0], s[1:]
-	return sign + '0'*(width-n) + s
+    """
+    if type(x) == type(''): s = x
+    else: s = `x`
+    n = len(s)
+    if n >= width: return s
+    sign = ''
+    if s[0] in ('-', '+'):
+	sign, s = s[0], s[1:]
+    return sign + '0'*(width-n) + s
 
 # 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).
-
-	"""
-	res = line = ''
-	for c in s:
-		if c == '\t':
-			c = ' '*(tabsize - len(line)%tabsize)
-		line = line + c
-		if c == '\n':
-			res = res + line
-			line = ''
-	return res + line
+    """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).
+
+    """
+    res = line = ''
+    for c in s:
+	if c == '\t':
+	    c = ' '*(tabsize - len(line) % tabsize)
+	line = line + c
+	if c == '\n':
+	    res = res + line
+	    line = ''
+    return res + line
 
 # Character translation through look-up table.
 def translate(s, table, deletions=""):
-	"""translate(s,table [,deletechars]) -> string
-
-	Return a copy of the string s, where all characters occurring
-	in the optional argument deletechars are removed, and the
-	remaining characters have been mapped through the given
-	translation table, which must be a string of length 256.
-
-	"""
-	if type(table) != type('') or len(table) != 256:
-		raise TypeError, \
-		      "translation table must be 256 characters long"
-	res = ""
-	for c in s:
-		if c not in deletions:
-			res = res + table[ord(c)]
-	return res
+    """translate(s,table [,deletechars]) -> string
+
+    Return a copy of the string s, where all characters occurring
+    in the optional argument deletechars are removed, and the
+    remaining characters have been mapped through the given
+    translation table, which must be a string of length 256.
+
+    """
+    return s.translate(table, deletions)
 
 # Capitalize a string, e.g. "aBc  dEf" -> "Abc  def".
 def capitalize(s):
-	"""capitalize(s) -> string
+    """capitalize(s) -> string
 
-	Return a copy of the string s with only its first character
-	capitalized.
+    Return a copy of the string s with only its first character
+    capitalized.
 
-	"""
-	return upper(s[:1]) + lower(s[1:])
+    """
+    return s.capitalize()
 
 # Capitalize the words in a string, e.g. " aBc  dEf " -> "Abc Def".
 # See also regsub.capwords().
 def capwords(s, sep=None):
-	"""capwords(s, [sep]) -> string
+    """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.
+    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 join(map(capitalize, split(s, sep)), sep or ' ')
+    """
+    return join(map(capitalize, s.split(sep)), sep or ' ')
 
 # 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 = map(None, _idmap)
-	L = _idmapL[:]
-	fromstr = map(ord, fromstr)
-	for i in range(len(fromstr)):
-		L[fromstr[i]] = tostr[i]
-	return joinfields(L, "")
+    """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 = map(None, _idmap)
+    L = _idmapL[:]
+    fromstr = map(ord, fromstr)
+    for i in range(len(fromstr)):
+	L[fromstr[i]] = tostr[i]
+    return joinfields(L, "")
 
 # Substring replacement (global)
-def replace(str, old, new, maxsplit=0):
-	"""replace (str, old, new[, maxsplit]) -> string
+def replace(s, old, new, maxsplit=0):
+    """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 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 joinfields(splitfields(str, old, maxsplit), new)
+    """
+    return s.replace(old, new, maxsplit)
 
 
+# XXX: transitional
+#
+# If string objects do not have methods, then we need to use the old string.py
+# library, which uses strop for many more things than just the few outlined
+# below.
+try:
+    ''.upper
+except AttributeError:
+    from stringold import *
+
 # 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 *
-	letters = lowercase + uppercase
+    from strop import maketrans, lowercase, uppercase, whitespace
+    letters = lowercase + uppercase
 except ImportError:
-	pass # Use the original, slow versions
+    pass					  # Use the original versions