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made palatable for latex2html: 

removed $math$, added braces to \item[\tt...]
This commit is contained in:
Guido van Rossum 1995-03-16 14:44:07 +00:00
parent a521c1b751
commit a54754719d
8 changed files with 186 additions and 172 deletions
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2
Doc/ref.tex
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@ -1,4 +1,4 @@
\documentstyle[twoside,11pt,myformat]{report}
\documentstyle[twoside,11pt,myformat,html]{report}
\title{Python Reference Manual}

2
Doc/ref/ref.tex
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@ -1,4 +1,4 @@
\documentstyle[twoside,11pt,myformat]{report}
\documentstyle[twoside,11pt,myformat,html]{report}
\title{Python Reference Manual}

11
Doc/ref/ref2.tex
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@ -294,11 +294,12 @@ Although both lower case `l' and upper case `L' are allowed as suffix
for long integers, it is strongly recommended to always use `L', since
the letter `l' looks too much like the digit `1'.
Plain integer decimal literals must be at most $2^{31} - 1$ (i.e., the
largest positive integer, assuming 32-bit arithmetic). Plain octal and
hexadecimal literals may be as large as $2^{32} - 1$, but values
larger than $2^{31} - 1$ are converted to a negative value by
subtracting $2^{32}$. There is no limit for long integer literals.
Plain integer decimal literals must be at most 2147483647 (i.e., the
largest positive integer, using 32-bit arithmetic). Plain octal and
hexadecimal literals may be as large as 4294967295, but values larger
than 2147483647 are converted to a negative value by subtracting
4294967296. There is no limit for long integer literals apart from
what can be stored in available memory.
Some examples of plain and long integer literals:

97
Doc/ref/ref3.tex
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@ -130,14 +130,14 @@ There are two types of integers:
\begin{description}
\item[Plain integers]
These represent numbers in the range $-2^{31}$ through $2^{31}-1$.
These represent numbers in the range -2147483648 through 2147483647.
(The range may be larger on machines with a larger natural word
size, but not smaller.)
When the result of an operation falls outside this range, the
exception \verb@OverflowError@ is raised.
For the purpose of shift and mask operations, integers are assumed to
have a binary, 2's complement notation using 32 or more bits, and
hiding no bits from the user (i.e., all $2^{32}$ different bit
hiding no bits from the user (i.e., all 4294967296 different bit
patterns correspond to different values).
\obindex{plain integer}
@ -173,9 +173,9 @@ C implementation for the accepted range and handling of overflow.
\item[Sequences]
These represent finite ordered sets indexed by natural numbers.
The built-in function \verb@len()@ returns the number of elements
of a sequence. When this number is $n$, the index set contains
the numbers $0, 1, \ldots, n-1$. Element \verb@i@ of sequence
\verb@a@ is selected by \verb@a[i]@.
of a sequence. When this number is \var{n}, the index set contains
the numbers 0, 1, \ldots, \var{n}-1. Element \var{i} of sequence
\var{a} is selected by \code{\var{a}[\var{i}]}.
\obindex{seqence}
\bifuncindex{len}
\index{index operation}
@ -183,9 +183,10 @@ the numbers $0, 1, \ldots, n-1$. Element \verb@i@ of sequence
\index{subscription}
Sequences also support slicing: \verb@a[i:j]@ selects all elements
with index $k$ such that $i <= k < j$. When used as an expression,
a slice is a sequence of the same type --- this implies that the
index set is renumbered so that it starts at 0 again.
with index \var{k} such that \var{i} \code{<=} \var{k} \code{<}
\var{j}. When used as an expression, a slice is a sequence of the
same type --- this implies that the index set is renumbered so that it
starts at 0 again.
\index{slicing}
Sequences are distinguished according to their mutability:
@ -599,14 +600,14 @@ For \verb@__str__@, the default is to use \verb@__repr__@.
\begin{description}
\item[\tt __init__(self, args...)]
\item[{\tt __init__(self, args...)}]
Called when the instance is created. The arguments are those passed
to the class constructor expression. If a base class has an
\code{__init__} method the derived class's \code{__init__} method must
explicitly call it to ensure proper initialization of the base class
part of the instance.
\item[\tt __del__(self)]
\item[{\tt __del__(self)}]
Called when the instance is about to be destroyed. If a base class
has an \code{__del__} method the derived class's \code{__del__} method
must explicitly call it to ensure proper deletion of the base class
@ -621,7 +622,7 @@ Note that \code{del x} doesn't directly call \code{x.__del__} --- the
former decrements the reference count for \code{x} by one, but
\code{x,__del__} is only called when its reference count reaches zero.
\item[\tt __repr__(self)]
\item[{\tt __repr__(self)}]
Called by the \verb@repr()@ built-in function and by string conversions
(reverse or backward quotes) to compute the string representation of an object.
\indexii{string}{conversion}
@ -629,11 +630,11 @@ Called by the \verb@repr()@ built-in function and by string conversions
\indexii{backward}{quotes}
\index{back-quotes}
\item[\tt __str__(self)]
\item[{\tt __str__(self)}]
Called by the \verb@str()@ built-in function and by the \verb@print@
statement compute the string representation of an object.
\item[\tt __cmp__(self, other)]
\item[{\tt __cmp__(self, other)}]
Called by all comparison operations. Should return -1 if
\verb@self < other@, 0 if \verb@self == other@, +1 if
\verb@self > other@. If no \code{__cmp__} operation is defined, class
@ -642,7 +643,7 @@ instances are compared by object identity (``address'').
exceptions raised by comparisons are ignored, and the objects will be
considered equal in this case.)
\item[\tt __hash__(self)]
\item[{\tt __hash__(self)}]
Called for the key object for dictionary operations,
and by the built-in function
\code{hash()}. Should return a 32-bit integer usable as a hash value
@ -659,7 +660,7 @@ implements a \code{__cmp__} method it should not implement
key's hash value is a constant.
\obindex{dictionary}
\item[\tt __call__(self, *args)]
\item[{\tt __call__(self, *args)}]
Called when the instance is ``called'' as a function.
\end{description}
@ -672,7 +673,7 @@ access for class instances.
\begin{description}
\item[\tt __getattr__(self, name)]
\item[{\tt __getattr__(self, name)}]
Called when an attribute lookup has not found the attribute in the
usual places (i.e. it is not an instance attribute nor is it found in
the class tree for \code{self}). \code{name} is the attribute name.
@ -687,7 +688,7 @@ Note that at least for instance variables, \code{__getattr__} can fake
total control by simply not inserting any values in the instance
attribute dictionary.
\item[\tt __setattr__(self, name, value)]
\item[{\tt __setattr__(self, name, value)}]
Called when an attribute assignment is attempted. This is called
instead of the normal mechanism (i.e. store the value as an instance
attribute). \code{name} is the attribute name, \code{value} is the
@ -699,7 +700,7 @@ cause a recursive call. Instead, it should insert the value in the
dictionary of instance attributes, e.g. \code{self.__dict__[name] =
value}.
\item[\tt __delattr__(self, name)]
\item[{\tt __delattr__(self, name)}]
Like \code{__setattr__} but for attribute deletion instead of
assignment.
@ -710,22 +711,22 @@ assignment.
\begin{description}
\item[\tt __len__(self)]
\item[{\tt __len__(self)}]
Called to implement the built-in function \verb@len()@. Should return
the length of the object, an integer \verb@>=@ 0. Also, an object
whose \verb@__len__()@ method returns 0 is considered to be false in a
Boolean context.
\item[\tt __getitem__(self, key)]
\item[{\tt __getitem__(self, key)}]
Called to implement evaluation of \verb@self[key]@. Note that the
special interpretation of negative keys (if the class wishes to
emulate a sequence type) is up to the \verb@__getitem__@ method.
\item[\tt __setitem__(self, key, value)]
\item[{\tt __setitem__(self, key, value)}]
Called to implement assignment to \verb@self[key]@. Same note as for
\verb@__getitem__@.
\item[\tt __delitem__(self, key)]
\item[{\tt __delitem__(self, key)}]
Called to implement deletion of \verb@self[key]@. Same note as for
\verb@__getitem__@.
@ -736,18 +737,18 @@ Called to implement deletion of \verb@self[key]@. Same note as for
\begin{description}
\item[\tt __getslice__(self, i, j)]
\item[{\tt __getslice__(self, i, j)}]
Called to implement evaluation of \verb@self[i:j]@. Note that missing
\verb@i@ or \verb@j@ are replaced by 0 or \verb@len(self)@,
respectively, and \verb@len(self)@ has been added (once) to originally
negative \verb@i@ or \verb@j@ by the time this function is called
(unlike for \verb@__getitem__@).
\item[\tt __setslice__(self, i, j, sequence)]
\item[{\tt __setslice__(self, i, j, sequence)}]
Called to implement assignment to \verb@self[i:j]@. Same notes as for
\verb@__getslice__@.
\item[\tt __delslice__(self, i, j)]
\item[{\tt __delslice__(self, i, j)}]
Called to implement deletion of \verb@self[i:j]@. Same notes as for
\verb@__getslice__@.
@ -758,34 +759,34 @@ Called to implement deletion of \verb@self[i:j]@. Same notes as for
\begin{description}
\item[\tt __add__(self, other)]\itemjoin
\item[\tt __sub__(self, other)]\itemjoin
\item[\tt __mul__(self, other)]\itemjoin
\item[\tt __div__(self, other)]\itemjoin
\item[\tt __mod__(self, other)]\itemjoin
\item[\tt __divmod__(self, other)]\itemjoin
\item[\tt __pow__(self, other)]\itemjoin
\item[\tt __lshift__(self, other)]\itemjoin
\item[\tt __rshift__(self, other)]\itemjoin
\item[\tt __and__(self, other)]\itemjoin
\item[\tt __xor__(self, other)]\itemjoin
\item[\tt __or__(self, other)]\itembreak
\item[{\tt __add__(self, other)}]\itemjoin
\item[{\tt __sub__(self, other)}]\itemjoin
\item[{\tt __mul__(self, other)}]\itemjoin
\item[{\tt __div__(self, other)}]\itemjoin
\item[{\tt __mod__(self, other)}]\itemjoin
\item[{\tt __divmod__(self, other)}]\itemjoin
\item[{\tt __pow__(self, other)}]\itemjoin
\item[{\tt __lshift__(self, other)}]\itemjoin
\item[{\tt __rshift__(self, other)}]\itemjoin
\item[{\tt __and__(self, other)}]\itemjoin
\item[{\tt __xor__(self, other)}]\itemjoin
\item[{\tt __or__(self, other)}]\itembreak
Called to implement the binary arithmetic operations (\verb@+@,
\verb@-@, \verb@*@, \verb@/@, \verb@%@, \verb@divmod()@, \verb@pow()@,
\verb@<<@, \verb@>>@, \verb@&@, \verb@^@, \verb@|@).
\item[\tt __neg__(self)]\itemjoin
\item[\tt __pos__(self)]\itemjoin
\item[\tt __abs__(self)]\itemjoin
\item[\tt __invert__(self)]\itembreak
\item[{\tt __neg__(self)}]\itemjoin
\item[{\tt __pos__(self)}]\itemjoin
\item[{\tt __abs__(self)}]\itemjoin
\item[{\tt __invert__(self)}]\itembreak
Called to implement the unary arithmetic operations (\verb@-@, \verb@+@,
\verb@abs()@ and \verb@~@).
\item[\tt __nonzero__(self)]
\item[{\tt __nonzero__(self)}]
Called to implement boolean testing; should return 0 or 1. An
alternative name for this method is \verb@__len__@.
\item[\tt __coerce__(self, other)]
\item[{\tt __coerce__(self, other)}]
Called to implement ``mixed-mode'' numeric arithmetic. Should either
return a tuple containing self and other converted to a common numeric
type, or None if no way of conversion is known. When the common type
@ -803,14 +804,14 @@ same reason, in \verb@n*x@, where \verb@n@ is a built-in number and
user-defined classes implementing sequences, mappings or numbers, but
currently it doesn't --- hence this strange exception.}
\item[\tt __int__(self)]\itemjoin
\item[\tt __long__(self)]\itemjoin
\item[\tt __float__(self)]\itembreak
\item[{\tt __int__(self)}]\itemjoin
\item[{\tt __long__(self)}]\itemjoin
\item[{\tt __float__(self)}]\itembreak
Called to implement the built-in functions \verb@int()@, \verb@long()@
and \verb@float()@. Should return a value of the appropriate type.
\item[\tt __oct__(self)]\itemjoin
\item[\tt __hex__(self)]\itembreak
\item[{\tt __oct__(self)}]\itemjoin
\item[{\tt __hex__(self)}]\itembreak
Called to implement the built-in functions \verb@oct()@ and
\verb@hex()@. Should return a string value.

69
Doc/ref/ref5.tex
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@ -307,9 +307,10 @@ The primary must evaluate to a sequence object. The lower and upper
bound expressions, if present, must evaluate to plain integers;
defaults are zero and the sequence's length, respectively. If either
bound is negative, the sequence's length is added to it. The slicing
now selects all items with index $k$ such that $i <= k < j$ where $i$
and $j$ are the specified lower and upper bounds. This may be an
empty sequence. It is not an error if $i$ or $j$ lie outside the
now selects all items with index \var{k} such that
\code{\var{i} <= \var{k} < \var{j}} where \var{i}
and \var{j} are the specified lower and upper bounds. This may be an
empty sequence. It is not an error if \var{i} or \var{j} lie outside the
range of valid indexes (such items don't exist so they aren't
selected).
@ -477,10 +478,11 @@ arguments are converted to a common type. They shift the first
argument to the left or right by the number of bits given by the
second argument.
A right shift by $n$ bits is defined as division by $2^n$. A left
shift by $n$ bits is defined as multiplication with $2^n$; for plain
integers there is no overflow check so this drops bits and flip the
sign if the result is not less than $2^{31}$ in absolute value.
A right shift by \var{n} bits is defined as division by
\code{pow(2,\var{n})}. A left shift by \var{n} bits is defined as
multiplication with \code{pow(2,\var{n})}; for plain integers there is
no overflow check so this drops bits and flips the sign if the result
is not less than \code{pow(2,31)} in absolute value.
Negative shift counts raise a \verb@ValueError@ exception.
\exindex{ValueError}
@ -530,20 +532,21 @@ comp_operator: "<"|">"|"=="|">="|"<="|"<>"|"!="|"is" ["not"]|["not"] "in"
Comparisons yield integer values: 1 for true, 0 for false.
Comparisons can be chained arbitrarily, e.g. $x < y <= z$ is
equivalent to $x < y$ \verb@and@ $y <= z$, except that $y$ is
evaluated only once (but in both cases $z$ is not evaluated at all
when $x < y$ is found to be false).
Comparisons can be chained arbitrarily, e.g. \code{x < y <= z} is
equivalent to \code{x < y and y <= z}, except that \code{y} is
evaluated only once (but in both cases \code{z} is not evaluated at all
when \code{x < y} is found to be false).
\indexii{chaining}{comparisons}
\catcode`\_=8
Formally, $e_0 op_1 e_1 op_2 e_2 ...e_{n-1} op_n e_n$ is equivalent to
$e_0 op_1 e_1$ \verb@and@ $e_1 op_2 e_2$ \verb@and@ ... \verb@and@
$e_{n-1} op_n e_n$, except that each expression is evaluated at most once.
Formally, if \var{a}, \var{b}, \var{c}, \ldots, \var{y}, \var{z} are
expressions and \var{opa}, \var{opb}, \ldots, \var{opy} are comparison
operators, then \var{a opa b opb c} \ldots \var{y opy z} is equivalent
to \var{a opa b} \code{and} \var{b opb c} \code{and} \ldots \code{and}
\var{y opy z}, except that each expression is evaluated at most once.
Note that $e_0 op_1 e_1 op_2 e_2$ does not imply any kind of comparison
between $e_0$ and $e_2$, e.g. $x < y > z$ is perfectly legal.
\catcode`\_=12
Note that \var{a opa b opb c} doesn't imply any kind of comparison
between \var{a} and \var{c}, so that e.g.\ \code{x < y > z} is
perfectly legal (though perhaps not pretty).
The forms \verb@<>@ and \verb@!=@ are equivalent; for consistency with
C, \verb@!=@ is preferred; where \verb@!=@ is mentioned below
@ -557,7 +560,7 @@ ordered consistently but arbitrarily.
(This unusual definition of comparison is done to simplify the
definition of operations like sorting and the \verb@in@ and
\verb@not in@ operators.)
\verb@not@ \verb@in@ operators.)
Comparison of objects of the same type depends on the type:
@ -592,11 +595,12 @@ execution of a program.
\end{itemize}
The operators \verb@in@ and \verb@not in@ test for sequence
membership: if $y$ is a sequence, $x ~\verb@in@~ y$ is true if and
only if there exists an index $i$ such that $x = y[i]$.
$x ~\verb@not in@~ y$ yields the inverse truth value. The exception
\verb@TypeError@ is raised when $y$ is not a sequence, or when $y$ is
a string and $x$ is not a string of length one.%
membership: if \var{y} is a sequence, \code{\var{x} in \var{y}} is
true if and only if there exists an index \var{i} such that
\code{\var{x} = \var{y}[\var{i}]}.
\code{\var{x} not in \var{y}} yields the inverse truth value. The
exception \verb@TypeError@ is raised when \var{y} is not a sequence,
or when \var{y} is a string and \var{x} is not a string of length one.%
\footnote{The latter restriction is sometimes a nuisance.}
\opindex{in}
\opindex{not in}
@ -604,8 +608,9 @@ a string and $x$ is not a string of length one.%
\obindex{sequence}
The operators \verb@is@ and \verb@is not@ test for object identity:
$x ~\verb@is@~ y$ is true if and only if $x$ and $y$ are the same
object. $x ~\verb@is not@~ y$ yields the inverse truth value.
\var{x} \code{is} \var{y} is true if and only if \var{x} and \var{y}
are the same object. \var{x} \code{is not} \var{y} yields the inverse
truth value.
\opindex{is}
\opindex{is not}
\indexii{identity}{test}
@ -632,14 +637,14 @@ other values are interpreted as true.
The operator \verb@not@ yields 1 if its argument is false, 0 otherwise.
\opindex{not}
The condition $x ~\verb@and@~ y$ first evaluates $x$; if $x$ is false,
its value is returned; otherwise, $y$ is evaluated and the resulting
value is returned.
The condition \var{x} \verb@and@ \var{y} first evaluates \var{x}; if
\var{x} is false, its value is returned; otherwise, \var{y} is
evaluated and the resulting value is returned.
\opindex{and}
The condition $x ~\verb@or@~ y$ first evaluates $x$; if $x$ is true,
its value is returned; otherwise, $y$ is evaluated and the resulting
value is returned.
The condition \var{x} \verb@or@ \var{y} first evaluates \var{x}; if
\var{x} is true, its value is returned; otherwise, \var{y} is
evaluated and the resulting value is returned.
\opindex{or}
(Note that \verb@and@ and \verb@or@ do not restrict the value and type

11
Doc/ref2.tex
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@ -294,11 +294,12 @@ Although both lower case `l' and upper case `L' are allowed as suffix
for long integers, it is strongly recommended to always use `L', since
the letter `l' looks too much like the digit `1'.
Plain integer decimal literals must be at most $2^{31} - 1$ (i.e., the
largest positive integer, assuming 32-bit arithmetic). Plain octal and
hexadecimal literals may be as large as $2^{32} - 1$, but values
larger than $2^{31} - 1$ are converted to a negative value by
subtracting $2^{32}$. There is no limit for long integer literals.
Plain integer decimal literals must be at most 2147483647 (i.e., the
largest positive integer, using 32-bit arithmetic). Plain octal and
hexadecimal literals may be as large as 4294967295, but values larger
than 2147483647 are converted to a negative value by subtracting
4294967296. There is no limit for long integer literals apart from
what can be stored in available memory.
Some examples of plain and long integer literals:

97
Doc/ref3.tex
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@ -130,14 +130,14 @@ There are two types of integers:
\begin{description}
\item[Plain integers]
These represent numbers in the range $-2^{31}$ through $2^{31}-1$.
These represent numbers in the range -2147483648 through 2147483647.
(The range may be larger on machines with a larger natural word
size, but not smaller.)
When the result of an operation falls outside this range, the
exception \verb@OverflowError@ is raised.
For the purpose of shift and mask operations, integers are assumed to
have a binary, 2's complement notation using 32 or more bits, and
hiding no bits from the user (i.e., all $2^{32}$ different bit
hiding no bits from the user (i.e., all 4294967296 different bit
patterns correspond to different values).
\obindex{plain integer}
@ -173,9 +173,9 @@ C implementation for the accepted range and handling of overflow.
\item[Sequences]
These represent finite ordered sets indexed by natural numbers.
The built-in function \verb@len()@ returns the number of elements
of a sequence. When this number is $n$, the index set contains
the numbers $0, 1, \ldots, n-1$. Element \verb@i@ of sequence
\verb@a@ is selected by \verb@a[i]@.
of a sequence. When this number is \var{n}, the index set contains
the numbers 0, 1, \ldots, \var{n}-1. Element \var{i} of sequence
\var{a} is selected by \code{\var{a}[\var{i}]}.
\obindex{seqence}
\bifuncindex{len}
\index{index operation}
@ -183,9 +183,10 @@ the numbers $0, 1, \ldots, n-1$. Element \verb@i@ of sequence
\index{subscription}
Sequences also support slicing: \verb@a[i:j]@ selects all elements
with index $k$ such that $i <= k < j$. When used as an expression,
a slice is a sequence of the same type --- this implies that the
index set is renumbered so that it starts at 0 again.
with index \var{k} such that \var{i} \code{<=} \var{k} \code{<}
\var{j}. When used as an expression, a slice is a sequence of the
same type --- this implies that the index set is renumbered so that it
starts at 0 again.
\index{slicing}
Sequences are distinguished according to their mutability:
@ -599,14 +600,14 @@ For \verb@__str__@, the default is to use \verb@__repr__@.
\begin{description}
\item[\tt __init__(self, args...)]
\item[{\tt __init__(self, args...)}]
Called when the instance is created. The arguments are those passed
to the class constructor expression. If a base class has an
\code{__init__} method the derived class's \code{__init__} method must
explicitly call it to ensure proper initialization of the base class
part of the instance.
\item[\tt __del__(self)]
\item[{\tt __del__(self)}]
Called when the instance is about to be destroyed. If a base class
has an \code{__del__} method the derived class's \code{__del__} method
must explicitly call it to ensure proper deletion of the base class
@ -621,7 +622,7 @@ Note that \code{del x} doesn't directly call \code{x.__del__} --- the
former decrements the reference count for \code{x} by one, but
\code{x,__del__} is only called when its reference count reaches zero.
\item[\tt __repr__(self)]
\item[{\tt __repr__(self)}]
Called by the \verb@repr()@ built-in function and by string conversions
(reverse or backward quotes) to compute the string representation of an object.
\indexii{string}{conversion}
@ -629,11 +630,11 @@ Called by the \verb@repr()@ built-in function and by string conversions
\indexii{backward}{quotes}
\index{back-quotes}
\item[\tt __str__(self)]
\item[{\tt __str__(self)}]
Called by the \verb@str()@ built-in function and by the \verb@print@
statement compute the string representation of an object.
\item[\tt __cmp__(self, other)]
\item[{\tt __cmp__(self, other)}]
Called by all comparison operations. Should return -1 if
\verb@self < other@, 0 if \verb@self == other@, +1 if
\verb@self > other@. If no \code{__cmp__} operation is defined, class
@ -642,7 +643,7 @@ instances are compared by object identity (``address'').
exceptions raised by comparisons are ignored, and the objects will be
considered equal in this case.)
\item[\tt __hash__(self)]
\item[{\tt __hash__(self)}]
Called for the key object for dictionary operations,
and by the built-in function
\code{hash()}. Should return a 32-bit integer usable as a hash value
@ -659,7 +660,7 @@ implements a \code{__cmp__} method it should not implement
key's hash value is a constant.
\obindex{dictionary}
\item[\tt __call__(self, *args)]
\item[{\tt __call__(self, *args)}]
Called when the instance is ``called'' as a function.
\end{description}
@ -672,7 +673,7 @@ access for class instances.
\begin{description}
\item[\tt __getattr__(self, name)]
\item[{\tt __getattr__(self, name)}]
Called when an attribute lookup has not found the attribute in the
usual places (i.e. it is not an instance attribute nor is it found in
the class tree for \code{self}). \code{name} is the attribute name.
@ -687,7 +688,7 @@ Note that at least for instance variables, \code{__getattr__} can fake
total control by simply not inserting any values in the instance
attribute dictionary.
\item[\tt __setattr__(self, name, value)]
\item[{\tt __setattr__(self, name, value)}]
Called when an attribute assignment is attempted. This is called
instead of the normal mechanism (i.e. store the value as an instance
attribute). \code{name} is the attribute name, \code{value} is the
@ -699,7 +700,7 @@ cause a recursive call. Instead, it should insert the value in the
dictionary of instance attributes, e.g. \code{self.__dict__[name] =
value}.
\item[\tt __delattr__(self, name)]
\item[{\tt __delattr__(self, name)}]
Like \code{__setattr__} but for attribute deletion instead of
assignment.
@ -710,22 +711,22 @@ assignment.
\begin{description}
\item[\tt __len__(self)]
\item[{\tt __len__(self)}]
Called to implement the built-in function \verb@len()@. Should return
the length of the object, an integer \verb@>=@ 0. Also, an object
whose \verb@__len__()@ method returns 0 is considered to be false in a
Boolean context.
\item[\tt __getitem__(self, key)]
\item[{\tt __getitem__(self, key)}]
Called to implement evaluation of \verb@self[key]@. Note that the
special interpretation of negative keys (if the class wishes to
emulate a sequence type) is up to the \verb@__getitem__@ method.
\item[\tt __setitem__(self, key, value)]
\item[{\tt __setitem__(self, key, value)}]
Called to implement assignment to \verb@self[key]@. Same note as for
\verb@__getitem__@.
\item[\tt __delitem__(self, key)]
\item[{\tt __delitem__(self, key)}]
Called to implement deletion of \verb@self[key]@. Same note as for
\verb@__getitem__@.
@ -736,18 +737,18 @@ Called to implement deletion of \verb@self[key]@. Same note as for
\begin{description}
\item[\tt __getslice__(self, i, j)]
\item[{\tt __getslice__(self, i, j)}]
Called to implement evaluation of \verb@self[i:j]@. Note that missing
\verb@i@ or \verb@j@ are replaced by 0 or \verb@len(self)@,
respectively, and \verb@len(self)@ has been added (once) to originally
negative \verb@i@ or \verb@j@ by the time this function is called
(unlike for \verb@__getitem__@).
\item[\tt __setslice__(self, i, j, sequence)]
\item[{\tt __setslice__(self, i, j, sequence)}]
Called to implement assignment to \verb@self[i:j]@. Same notes as for
\verb@__getslice__@.
\item[\tt __delslice__(self, i, j)]
\item[{\tt __delslice__(self, i, j)}]
Called to implement deletion of \verb@self[i:j]@. Same notes as for
\verb@__getslice__@.
@ -758,34 +759,34 @@ Called to implement deletion of \verb@self[i:j]@. Same notes as for
\begin{description}
\item[\tt __add__(self, other)]\itemjoin
\item[\tt __sub__(self, other)]\itemjoin
\item[\tt __mul__(self, other)]\itemjoin
\item[\tt __div__(self, other)]\itemjoin
\item[\tt __mod__(self, other)]\itemjoin
\item[\tt __divmod__(self, other)]\itemjoin
\item[\tt __pow__(self, other)]\itemjoin
\item[\tt __lshift__(self, other)]\itemjoin
\item[\tt __rshift__(self, other)]\itemjoin
\item[\tt __and__(self, other)]\itemjoin
\item[\tt __xor__(self, other)]\itemjoin
\item[\tt __or__(self, other)]\itembreak
\item[{\tt __add__(self, other)}]\itemjoin
\item[{\tt __sub__(self, other)}]\itemjoin
\item[{\tt __mul__(self, other)}]\itemjoin
\item[{\tt __div__(self, other)}]\itemjoin
\item[{\tt __mod__(self, other)}]\itemjoin
\item[{\tt __divmod__(self, other)}]\itemjoin
\item[{\tt __pow__(self, other)}]\itemjoin
\item[{\tt __lshift__(self, other)}]\itemjoin
\item[{\tt __rshift__(self, other)}]\itemjoin
\item[{\tt __and__(self, other)}]\itemjoin
\item[{\tt __xor__(self, other)}]\itemjoin
\item[{\tt __or__(self, other)}]\itembreak
Called to implement the binary arithmetic operations (\verb@+@,
\verb@-@, \verb@*@, \verb@/@, \verb@%@, \verb@divmod()@, \verb@pow()@,
\verb@<<@, \verb@>>@, \verb@&@, \verb@^@, \verb@|@).
\item[\tt __neg__(self)]\itemjoin
\item[\tt __pos__(self)]\itemjoin
\item[\tt __abs__(self)]\itemjoin
\item[\tt __invert__(self)]\itembreak
\item[{\tt __neg__(self)}]\itemjoin
\item[{\tt __pos__(self)}]\itemjoin
\item[{\tt __abs__(self)}]\itemjoin
\item[{\tt __invert__(self)}]\itembreak
Called to implement the unary arithmetic operations (\verb@-@, \verb@+@,
\verb@abs()@ and \verb@~@).
\item[\tt __nonzero__(self)]
\item[{\tt __nonzero__(self)}]
Called to implement boolean testing; should return 0 or 1. An
alternative name for this method is \verb@__len__@.
\item[\tt __coerce__(self, other)]
\item[{\tt __coerce__(self, other)}]
Called to implement ``mixed-mode'' numeric arithmetic. Should either
return a tuple containing self and other converted to a common numeric
type, or None if no way of conversion is known. When the common type
@ -803,14 +804,14 @@ same reason, in \verb@n*x@, where \verb@n@ is a built-in number and
user-defined classes implementing sequences, mappings or numbers, but
currently it doesn't --- hence this strange exception.}
\item[\tt __int__(self)]\itemjoin
\item[\tt __long__(self)]\itemjoin
\item[\tt __float__(self)]\itembreak
\item[{\tt __int__(self)}]\itemjoin
\item[{\tt __long__(self)}]\itemjoin
\item[{\tt __float__(self)}]\itembreak
Called to implement the built-in functions \verb@int()@, \verb@long()@
and \verb@float()@. Should return a value of the appropriate type.
\item[\tt __oct__(self)]\itemjoin
\item[\tt __hex__(self)]\itembreak
\item[{\tt __oct__(self)}]\itemjoin
\item[{\tt __hex__(self)}]\itembreak
Called to implement the built-in functions \verb@oct()@ and
\verb@hex()@. Should return a string value.

69
Doc/ref5.tex
View File

@ -307,9 +307,10 @@ The primary must evaluate to a sequence object. The lower and upper
bound expressions, if present, must evaluate to plain integers;
defaults are zero and the sequence's length, respectively. If either
bound is negative, the sequence's length is added to it. The slicing
now selects all items with index $k$ such that $i <= k < j$ where $i$
and $j$ are the specified lower and upper bounds. This may be an
empty sequence. It is not an error if $i$ or $j$ lie outside the
now selects all items with index \var{k} such that
\code{\var{i} <= \var{k} < \var{j}} where \var{i}
and \var{j} are the specified lower and upper bounds. This may be an
empty sequence. It is not an error if \var{i} or \var{j} lie outside the
range of valid indexes (such items don't exist so they aren't
selected).
@ -477,10 +478,11 @@ arguments are converted to a common type. They shift the first
argument to the left or right by the number of bits given by the
second argument.
A right shift by $n$ bits is defined as division by $2^n$. A left
shift by $n$ bits is defined as multiplication with $2^n$; for plain
integers there is no overflow check so this drops bits and flip the
sign if the result is not less than $2^{31}$ in absolute value.
A right shift by \var{n} bits is defined as division by
\code{pow(2,\var{n})}. A left shift by \var{n} bits is defined as
multiplication with \code{pow(2,\var{n})}; for plain integers there is
no overflow check so this drops bits and flips the sign if the result
is not less than \code{pow(2,31)} in absolute value.
Negative shift counts raise a \verb@ValueError@ exception.
\exindex{ValueError}
@ -530,20 +532,21 @@ comp_operator: "<"|">"|"=="|">="|"<="|"<>"|"!="|"is" ["not"]|["not"] "in"
Comparisons yield integer values: 1 for true, 0 for false.
Comparisons can be chained arbitrarily, e.g. $x < y <= z$ is
equivalent to $x < y$ \verb@and@ $y <= z$, except that $y$ is
evaluated only once (but in both cases $z$ is not evaluated at all
when $x < y$ is found to be false).
Comparisons can be chained arbitrarily, e.g. \code{x < y <= z} is
equivalent to \code{x < y and y <= z}, except that \code{y} is
evaluated only once (but in both cases \code{z} is not evaluated at all
when \code{x < y} is found to be false).
\indexii{chaining}{comparisons}
\catcode`\_=8
Formally, $e_0 op_1 e_1 op_2 e_2 ...e_{n-1} op_n e_n$ is equivalent to
$e_0 op_1 e_1$ \verb@and@ $e_1 op_2 e_2$ \verb@and@ ... \verb@and@
$e_{n-1} op_n e_n$, except that each expression is evaluated at most once.
Formally, if \var{a}, \var{b}, \var{c}, \ldots, \var{y}, \var{z} are
expressions and \var{opa}, \var{opb}, \ldots, \var{opy} are comparison
operators, then \var{a opa b opb c} \ldots \var{y opy z} is equivalent
to \var{a opa b} \code{and} \var{b opb c} \code{and} \ldots \code{and}
\var{y opy z}, except that each expression is evaluated at most once.
Note that $e_0 op_1 e_1 op_2 e_2$ does not imply any kind of comparison
between $e_0$ and $e_2$, e.g. $x < y > z$ is perfectly legal.
\catcode`\_=12
Note that \var{a opa b opb c} doesn't imply any kind of comparison
between \var{a} and \var{c}, so that e.g.\ \code{x < y > z} is
perfectly legal (though perhaps not pretty).
The forms \verb@<>@ and \verb@!=@ are equivalent; for consistency with
C, \verb@!=@ is preferred; where \verb@!=@ is mentioned below
@ -557,7 +560,7 @@ ordered consistently but arbitrarily.
(This unusual definition of comparison is done to simplify the
definition of operations like sorting and the \verb@in@ and
\verb@not in@ operators.)
\verb@not@ \verb@in@ operators.)
Comparison of objects of the same type depends on the type:
@ -592,11 +595,12 @@ execution of a program.
\end{itemize}
The operators \verb@in@ and \verb@not in@ test for sequence
membership: if $y$ is a sequence, $x ~\verb@in@~ y$ is true if and
only if there exists an index $i$ such that $x = y[i]$.
$x ~\verb@not in@~ y$ yields the inverse truth value. The exception
\verb@TypeError@ is raised when $y$ is not a sequence, or when $y$ is
a string and $x$ is not a string of length one.%
membership: if \var{y} is a sequence, \code{\var{x} in \var{y}} is
true if and only if there exists an index \var{i} such that
\code{\var{x} = \var{y}[\var{i}]}.
\code{\var{x} not in \var{y}} yields the inverse truth value. The
exception \verb@TypeError@ is raised when \var{y} is not a sequence,
or when \var{y} is a string and \var{x} is not a string of length one.%
\footnote{The latter restriction is sometimes a nuisance.}
\opindex{in}
\opindex{not in}
@ -604,8 +608,9 @@ a string and $x$ is not a string of length one.%
\obindex{sequence}
The operators \verb@is@ and \verb@is not@ test for object identity:
$x ~\verb@is@~ y$ is true if and only if $x$ and $y$ are the same
object. $x ~\verb@is not@~ y$ yields the inverse truth value.
\var{x} \code{is} \var{y} is true if and only if \var{x} and \var{y}
are the same object. \var{x} \code{is not} \var{y} yields the inverse
truth value.
\opindex{is}
\opindex{is not}
\indexii{identity}{test}
@ -632,14 +637,14 @@ other values are interpreted as true.
The operator \verb@not@ yields 1 if its argument is false, 0 otherwise.
\opindex{not}
The condition $x ~\verb@and@~ y$ first evaluates $x$; if $x$ is false,
its value is returned; otherwise, $y$ is evaluated and the resulting
value is returned.
The condition \var{x} \verb@and@ \var{y} first evaluates \var{x}; if
\var{x} is false, its value is returned; otherwise, \var{y} is
evaluated and the resulting value is returned.
\opindex{and}
The condition $x ~\verb@or@~ y$ first evaluates $x$; if $x$ is true,
its value is returned; otherwise, $y$ is evaluated and the resulting
value is returned.
The condition \var{x} \verb@or@ \var{y} first evaluates \var{x}; if
\var{x} is true, its value is returned; otherwise, \var{y} is
evaluated and the resulting value is returned.
\opindex{or}
(Note that \verb@and@ and \verb@or@ do not restrict the value and type