Python入門的36個例子——02 Help! —— 如何擷取協助

# 002<br /># 擷取命令的協助資訊時別忘了加上引號<br />help('print')<br /># 對於某種類型的資訊不用加引號，因為編譯器不可能把它理解成一個方法（函數）<br />help(str)

 

Output:

The “print“ statement
***********************

print_stmt ::= “print” ([expression ("," expression)* [","]]
| “>>” expression [("," expression)+ [","]])

“print“ evaluates each expression in turn and writes the resulting
object to standard output (see below). If an object is not a string,
it is first converted to a string using the rules for string
conversions. The (resulting or original) string is then written. A
space is written before each object is (converted and) written, unless
the output system believes it is positioned at the beginning of a
line. This is the case (1) when no characters have yet been written
to standard output, (2) when the last character written to standard
output is “’/n’“, or (3) when the last write operation on standard
output was not a “print“ statement. (In some cases it may be
functional to write an empty string to standard output for this
reason.)

Note: Objects which act like file objects but which are not the built-in
file objects often do not properly emulate this aspect of the file
object’s behavior, so it is best not to rely on this.

A “’/n’“ character is written at the end, unless the “print“
statement ends with a comma. This is the only action if the statement
contains just the keyword “print“.

Standard output is defined as the file object named “stdout“ in the
built-in module “sys“. If no such object exists, or if it does not
have a “write()“ method, a “RuntimeError“ exception is raised.

“print“ also has an extended form, defined by the second portion of
the syntax described above. This form is sometimes referred to as
““print“ chevron.” In this form, the first expression after the
“>>“ must evaluate to a “file-like” object, specifically an object
that has a “write()“ method as described above. With this extended
form, the subsequent expressions are printed to this file object. If
the first expression evaluates to “None“, then “sys.stdout“ is
used as the file for output.

Help on class str in module __builtin__:

class str(basestring)
| str(object) -> string
|
| Return a nice string representation of the object.
| If the argument is a string, the return value is the same object.
|
| Method resolution order:
| str
| basestring
| object
|
| Methods defined here:
|
| __add__(…)
| x.__add__(y) <==> x+y
|
| __contains__(…)
| x.__contains__(y) <==> y in x
|
| __eq__(…)
| x.__eq__(y) <==> x==y
|
| __format__(…)
| S.__format__(format_spec) -> unicode
|
| __ge__(…)
| x.__ge__(y) <==> x>=y
|
| __getattribute__(…)
| x.__getattribute__(’name’) <==> x.name
|
| __getitem__(…)
| x.__getitem__(y) <==> x[y]
|
| __getnewargs__(…)
|
| __getslice__(…)
| x.__getslice__(i, j) <==> x[i:j]
|
| Use of negative indices is not supported.
|
| __gt__(…)
| x.__gt__(y) <==> x>y
|
| __hash__(…)
| x.__hash__() <==> hash(x)
|
| __le__(…)
| x.__le__(y) <==> x<=y
|
| __len__(...)
| x.__len__() <==> len(x)
|
| __lt__(…)
| x.__lt__(y) <==> x
|
| __mod__(...)
| x.__mod__(y) <==> x%y
|
| __mul__(…)
| x.__mul__(n) <==> x*n
|
| __ne__(…)
| x.__ne__(y) <==> x!=y
|
| __repr__(…)
| x.__repr__() <==> repr(x)
|
| __rmod__(…)
| x.__rmod__(y) <==> y%x
|
| __rmul__(…)
| x.__rmul__(n) <==> n*x
|
| __sizeof__(…)
| S.__sizeof__() -> size of S in memory, in bytes
|
| __str__(…)
| x.__str__() <==> str(x)
|
| capitalize(…)
| S.capitalize() -> string
|
| Return a copy of the string S with only its first character
| capitalized.
|
| center(…)
| S.center(width[, fillchar]) -> string
|
| Return S centered in a string of length width. Padding is
| done using the specified fill character (default is a space)
|
| count(…)
| S.count(sub[, start[, end]]) -> int
|
| Return the number of non-overlapping occurrences of substring sub in
| string S[start:end]. Optional arguments start and end are interpreted
| as in slice notation.
|
| decode(…)
| S.decode([encoding[,errors]]) -> object
|
| Decodes S using the codec registered for encoding. encoding defaults
| to the default encoding. errors may be given to set a different error
| handling scheme. Default is ’strict’ meaning that encoding errors raise
| a UnicodeDecodeError. Other possible values are ‘ignore’ and ‘replace’
| as well as any other name registered with codecs.register_error that is
| able to handle UnicodeDecodeErrors.
|
| encode(…)
| S.encode([encoding[,errors]]) -> object
|
| Encodes S using the codec registered for encoding. encoding defaults
| to the default encoding. errors may be given to set a different error
| handling scheme. Default is ’strict’ meaning that encoding errors raise
| a UnicodeEncodeError. Other possible values are ‘ignore’, ‘replace’ and
| ‘xmlcharrefreplace’ as well as any other name registered with
| codecs.register_error that is able to handle UnicodeEncodeErrors.
|
| endswith(…)
| S.endswith(suffix[, start[, end]]) -> bool
|
| Return True if S ends with the specified suffix, False otherwise.
| With optional start, test S beginning at that position.
| With optional end, stop comparing S at that position.
| suffix can also be a tuple of strings to try.
|
| expandtabs(…)
| S.expandtabs([tabsize]) -> string
|
| Return a copy of S where all tab characters are expanded using spaces.
| If tabsize is not given, a tab size of 8 characters is assumed.
|
| find(…)
| S.find(sub [,start [,end]]) -> int
|
| 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.
|
| format(…)
| S.format(*args, **kwargs) -> unicode
|
| index(…)
| S.index(sub [,start [,end]]) -> int
|
| Like S.find() but raise ValueError when the substring is not found.
|
| isalnum(…)
| S.isalnum() -> bool
|
| Return True if all characters in S are alphanumeric
| and there is at least one character in S, False otherwise.
|
| isalpha(…)
| S.isalpha() -> bool
|
| Return True if all characters in S are alphabetic
| and there is at least one character in S, False otherwise.
|
| isdigit(…)
| S.isdigit() -> bool
|
| Return True if all characters in S are digits
| and there is at least one character in S, False otherwise.
|
| islower(…)
| S.islower() -> bool
|
| Return True if all cased characters in S are lowercase and there is
| at least one cased character in S, False otherwise.
|
| isspace(…)
| S.isspace() -> bool
|
| Return True if all characters in S are whitespace
| and there is at least one character in S, False otherwise.
|
| istitle(…)
| S.istitle() -> bool
|
| Return True if S is a titlecased string and there is at least one
| character in S, i.e. uppercase characters may only follow uncased
| characters and lowercase characters only cased ones. Return False
| otherwise.
|
| isupper(…)
| S.isupper() -> bool
|
| Return True if all cased characters in S are uppercase and there is
| at least one cased character in S, False otherwise.
|
| join(…)
| S.join(sequence) -> string
|
| Return a string which is the concatenation of the strings in the
| sequence. The separator between elements is S.
|
| ljust(…)
| S.ljust(width[, fillchar]) -> string
|
| Return S left-justified in a string of length width. Padding is
| done using the specified fill character (default is a space).
|
| lower(…)
| S.lower() -> string
|
| Return a copy of the string S converted to lowercase.
|
| lstrip(…)
| S.lstrip([chars]) -> string or unicode
|
| Return a copy of the string S with leading 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
|
| partition(…)
| S.partition(sep) -> (head, sep, tail)
|
| Search for the separator sep in S, and return the part before it,
| the separator itself, and the part after it. If the separator is not
| found, return S and two empty strings.
|
| replace(…)
| S.replace (old, new[, count]) -> string
|
| Return a copy of string S with all occurrences of substring
| old replaced by new. If the optional argument count is
| given, only the first count occurrences are replaced.
|
| rfind(…)
| S.rfind(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.
|
| rindex(…)
| S.rindex(sub [,start [,end]]) -> int
|
| Like S.rfind() but raise ValueError when the substring is not found.
|
| rjust(…)
| S.rjust(width[, fillchar]) -> string
|
| Return S right-justified in a string of length width. Padding is
| done using the specified fill character (default is a space)
|
| rpartition(…)
| S.rpartition(sep) -> (tail, sep, head)
|
| Search for the separator sep in S, starting at the end of S, and return
| the part before it, the separator itself, and the part after it. If the
| separator is not found, return two empty strings and S.
|
| rsplit(…)
| S.rsplit([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.
|
| rstrip(…)
| S.rstrip([chars]) -> string or unicode
|
| Return a copy of the string S with 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
|
| split(…)
| S.split([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, at most maxsplit
| splits are done. If sep is not specified or is None, any
| whitespace string is a separator and empty strings are removed
| from the result.
|
| splitlines(…)
| S.splitlines([keepends]) -> list of strings
|
| Return a list of the lines in S, breaking at line boundaries.
| Line breaks are not included in the resulting list unless keepends
| is given and true.
|
| startswith(…)
| S.startswith(prefix[, start[, end]]) -> bool
|
| Return True if S starts with the specified prefix, False otherwise.
| With optional start, test S beginning at that position.
| With optional end, stop comparing S at that position.
| prefix can also be a tuple of strings to try.
|
| strip(…)
| S.strip([chars]) -> string or unicode
|
| 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
|
| swapcase(…)
| S.swapcase() -> string
|
| Return a copy of the string S with uppercase characters
| converted to lowercase and vice versa.
|
| title(…)
| S.title() -> string
|
| Return a titlecased version of S, i.e. words start with uppercase
| characters, all remaining cased characters have lowercase.
|
| translate(…)
| S.translate(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.
|
| upper(…)
| S.upper() -> string
|
| Return a copy of the string S converted to uppercase.
|
| zfill(…)
| S.zfill(width) -> string
|
| Pad a numeric string S with zeros on the left, to fill a field
| of the specified width. The string S is never truncated.
|
| ———————————————————————-
| Data and other attributes defined here:
|
| __new__ =
| T.__new__(S, …) -> a new object with type S, a subtype of T