string
A language built-in type to support strings. Examples of string literals:a = 'abc\ndef' b = "ab'cd" c = """multiline string""" # Strings support slicing (negative index starts from the end): x = "hello"[2:4] # "ll" y = "hello"[1:-1] # "ell" z = "hello"[:4] # "hell"# Slice steps can be used, too: s = "hello"[::2] # "hlo" t = "hello"[3:0:-1] # "lle"Strings are not directly iterable, use the
.elems() method to iterate over their characters. Examples:"bc" in "abcd" # evaluates to True x = [s for s.elems() in "abc"] # x == ["a", "b", "c"]Implicit concatenation of strings is not allowed; use the
+ operator instead. Comparison operators perform a lexicographical comparison; use == to test for equality.
Members
capitalize
string string.capitalize()Returns a copy of the string with its first character (if any) capitalized and the rest lowercased. This method does not support non-ascii characters.
count
int string.count(sub, start=0, end=None)Returns the number of (non-overlapping) occurrences of substring
sub in string, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to count. |
start
|
Restrict to search from this position. |
end
|
optional position before which to restrict to search. |
elems
sequence string.elems()Returns an iterable value containing successive 1-element substrings of the string. Equivalent to
[s[i] for i in range(len(s))], except that the returned value might not be a list.
endswith
bool string.endswith(sub, start=0, end=None)Returns True if the string ends with
sub, otherwise False, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to check. |
start
|
Test beginning at this position. |
end
|
optional position at which to stop comparing. |
find
int string.find(sub, start=0, end=None)Returns the first index where
sub is found, or -1 if no such index exists, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to find. |
start
|
Restrict to search from this position. |
end
|
optional position before which to restrict to search. |
format
string string.format(*args, **kwargs)Perform string interpolation. Format strings contain replacement fields surrounded by curly braces
{}. Anything that is not contained in braces is considered literal text, which is copied unchanged to the output.If you need to include a brace character in the literal text, it can be escaped by doubling: {{ and }}A replacement field can be either a name, a number, or empty. Values are converted to strings using the str function.# Access in order:
"{} < {}".format(4, 5) == "4 < 5"
# Access by position:
"{1}, {0}".format(2, 1) == "1, 2"
# Access by name:
"x{key}x".format(key = 2) == "x2x"
Parameters
| Parameter | Description |
|---|---|
args
|
List of arguments. |
kwargs
|
Dictionary of arguments. |
index
int string.index(sub, start=0, end=None)Returns the first index where
sub is found, or raises an error if no such index exists, optionally restricting to [start:end]start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to find. |
start
|
Restrict to search from this position. |
end
|
optional position before which to restrict to search. |
isalnum
bool string.isalnum()Returns True if all characters in the string are alphanumeric ([a-zA-Z0-9]) and there is at least one character.
isalpha
bool string.isalpha()Returns True if all characters in the string are alphabetic ([a-zA-Z]) and there is at least one character.
isdigit
bool string.isdigit()Returns True if all characters in the string are digits ([0-9]) and there is at least one character.
islower
bool string.islower()Returns True if all cased characters in the string are lowercase and there is at least one character.
isspace
bool string.isspace()Returns True if all characters are white space characters and the string contains at least one character.
istitle
bool string.istitle()Returns True if the string is in title case and it contains at least one character. This means that every uppercase character must follow an uncased one (e.g. whitespace) and every lowercase character must follow a cased one (e.g. uppercase or lowercase).
isupper
bool string.isupper()Returns True if all cased characters in the string are uppercase and there is at least one character.
join
string string.join(elements)Returns a string in which the string elements of the argument have been joined by this string as a separator. Example:
"|".join(["a", "b", "c"]) == "a|b|c"
Parameters
| Parameter | Description |
|---|---|
elements
|
The objects to join. |
lower
string string.lower()Returns the lower case version of this string.
lstrip
string string.lstrip(chars=None)Returns a copy of the string where leading characters that appear in
chars are removed. Note that chars is not a prefix: all combinations of its value are removed:"abcba".lstrip("ba") == "cba"
Parameters
| Parameter | Description |
|---|---|
chars
|
The characters to remove, or all whitespace if None. |
partition
tuple string.partition(sep)Splits the input string at the first occurrence of the separator
sep and returns the resulting partition as a three-element tuple of the form (before, separator, after). If the input string does not contain the separator, partition returns (self, '', '').
Parameters
| Parameter | Description |
|---|---|
sep
|
The string to split on. |
replace
string string.replace(old, new, count=unbound)Returns a copy of the string in which the occurrences of
old have been replaced with new, optionally restricting the number of replacements to maxsplit.
Parameters
| Parameter | Description |
|---|---|
old
|
The string to be replaced. |
new
|
The string to replace with. |
count
|
The maximum number of replacements. If omitted, there is no limit. If |
rfind
int string.rfind(sub, start=0, end=None)Returns the last index where
sub is found, or -1 if no such index exists, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to find. |
start
|
Restrict to search from this position. |
end
|
optional position before which to restrict to search. |
rindex
int string.rindex(sub, start=0, end=None)Returns the last index where
sub is found, or raises an error if no such index exists, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring to find. |
start
|
Restrict to search from this position. |
end
|
optional position before which to restrict to search. |
rpartition
tuple string.rpartition(sep)Splits the input string at the last occurrence of the separator
sep and returns the resulting partition as a three-element tuple of the form (before, separator, after). If the input string does not contain the separator, rpartition returns ('', '', self).
Parameters
| Parameter | Description |
|---|---|
sep
|
The string to split on. |
rsplit
list string.rsplit(sep, maxsplit=None)Returns a list of all the words in the string, using
sep as the separator, optionally limiting the number of splits to maxsplit. Except for splitting from the right, this method behaves like split().
Parameters
| Parameter | Description |
|---|---|
sep
|
The string to split on. |
maxsplit
|
The maximum number of splits. |
rstrip
string string.rstrip(chars=None)Returns a copy of the string where trailing characters that appear in
chars are removed. Note that chars is not a suffix: all combinations of its value are removed:"abcbaa".rstrip("ab") == "abc"
Parameters
| Parameter | Description |
|---|---|
chars
|
The characters to remove, or all whitespace if None. |
split
list string.split(sep, maxsplit=None)Returns a list of all the words in the string, using
sep as the separator, optionally limiting the number of splits to maxsplit.
Parameters
| Parameter | Description |
|---|---|
sep
|
The string to split on. |
maxsplit
|
The maximum number of splits. |
splitlines
sequence string.splitlines(keepends=False)Splits the string at line boundaries ('\n', '\r\n', '\r') and returns the result as a list.
Parameters
| Parameter | Description |
|---|---|
keepends
|
Whether the line breaks should be included in the resulting list. |
startswith
bool string.startswith(sub, start=0, end=None)Returns True if the string starts with
sub, otherwise False, optionally restricting to [start:end], start being inclusive and end being exclusive.
Parameters
| Parameter | Description |
|---|---|
sub
|
The substring(s) to check. |
start
|
Test beginning at this position. |
end
|
Stop comparing at this position. |
strip
string string.strip(chars=None)Returns a copy of the string where leading or trailing characters that appear in
chars are removed. Note that chars is neither a prefix nor a suffix: all combinations of its value are removed:"aabcbcbaa".strip("ab") == "cbc"
Parameters
| Parameter | Description |
|---|---|
chars
|
The characters to remove, or all whitespace if None. |
title
string string.title()Converts the input string into title case, i.e. every word starts with an uppercase letter while the remaining letters are lowercase. In this context, a word means strictly a sequence of letters. This method does not support supplementary Unicode characters.
upper
string string.upper()Returns the upper case version of this string.