diff options
Diffstat (limited to 'Doc/ref')
| -rw-r--r-- | Doc/ref/ref2.tex | 43 | ||||
| -rw-r--r-- | Doc/ref/ref3.tex | 12 |
2 files changed, 24 insertions, 31 deletions
diff --git a/Doc/ref/ref2.tex b/Doc/ref/ref2.tex index 39b75a9..7b70676 100644 --- a/Doc/ref/ref2.tex +++ b/Doc/ref/ref2.tex @@ -565,6 +565,7 @@ number and an imaginary number). \index{floating point literal} \index{hexadecimal literal} \index{octal literal} +\index{binary literal} \index{decimal literal} \index{imaginary literal} \index{complex!literal} @@ -574,35 +575,32 @@ Note that numeric literals do not include a sign; a phrase like `\code{-}' and the literal \code{1}. -\subsection{Integer and long integer literals\label{integers}} +\subsection{Integer literals\label{integers}} -Integer and long integer literals are described by the following +Integer literals are described by the following lexical definitions: \begin{productionlist} - \production{longinteger} - {\token{integer} ("l" | "L")} \production{integer} {\token{decimalinteger} | \token{octinteger} | \token{hexinteger}} \production{decimalinteger} - {\token{nonzerodigit} \token{digit}* | "0"} + {\token{nonzerodigit} \token{digit}* | "0"+} \production{octinteger} - {"0" \token{octdigit}+} + {"0" ("o" | "O") \token{octdigit}+} \production{hexinteger} {"0" ("x" | "X") \token{hexdigit}+} + \production{bininteger} + {"0" ("b" | "B") \token{bindigit}+} \production{nonzerodigit} {"1"..."9"} \production{octdigit} {"0"..."7"} \production{hexdigit} {\token{digit} | "a"..."f" | "A"..."F"} + \production{bindigit} + {"0"..."1"} \end{productionlist} -Although both lower case \character{l} and upper case \character{L} are -allowed as suffix for long integers, it is strongly recommended to always -use \character{L}, since the letter \character{l} looks too much like the -digit \character{1}. - Plain integer literals that are above the largest representable plain integer (e.g., 2147483647 when using 32-bit arithmetic) are accepted as if they were long integers instead.\footnote{In versions of Python @@ -613,13 +611,16 @@ taken as the negative plain integer obtained by subtracting 4294967296 from their unsigned value.} There is no limit for long integer literals apart from what can be stored in available memory. -Some examples of plain integer literals (first row) and long integer -literals (second and third rows): +Note that leading zeros in a non-zero decimal number are not allowed. +This is for disambiguation with C-style octal literals, which Python +used before version 3.0. + +Some examples of integer literals: \begin{verbatim} -7 2147483647 0177 -3L 79228162514264337593543950336L 0377L 0x100000000L - 79228162514264337593543950336 0xdeadbeef +7 2147483647 0o177 0b100110111 +3 79228162514264337593543950336 0o377 0x100000000 + 79228162514264337593543950336 0xdeadbeef \end{verbatim} @@ -644,12 +645,10 @@ definitions: {("e" | "E") ["+" | "-"] \token{digit}+} \end{productionlist} -Note that the integer and exponent parts of floating point numbers -can look like octal integers, but are interpreted using radix 10. For -example, \samp{077e010} is legal, and denotes the same number -as \samp{77e10}. -The allowed range of floating point literals is -implementation-dependent. +Note that the integer and exponent parts are always interpreted using +radix 10. For example, \samp{077e010} is legal, and denotes the same +number as \samp{77e10}. +The allowed range of floating point literals is implementation-dependent. Some examples of floating point literals: \begin{verbatim} diff --git a/Doc/ref/ref3.tex b/Doc/ref/ref3.tex index 66aa273..cced29e 100644 --- a/Doc/ref/ref3.tex +++ b/Doc/ref/ref3.tex @@ -2033,17 +2033,11 @@ and \function{float()}\bifuncindex{float}. Should return a value of the appropriate type. \end{methoddesc} -\begin{methoddesc}[numeric object]{__oct__}{self} -\methodline[numeric object]{__hex__}{self} -Called to implement the built-in functions -\function{oct()}\bifuncindex{oct} and -\function{hex()}\bifuncindex{hex}. Should return a string value. -\end{methoddesc} - \begin{methoddesc}[numeric object]{__index__}{self} Called to implement \function{operator.index()}. Also called whenever -Python needs an integer object (such as in slicing). Must return an -integer (int or long). +Python needs an integer object (such as in slicing, or in the built-in +\function{bin()}, \function{hex()} and \function{oct()} functions). +Must return an integer (int or long). \versionadded{2.5} \end{methoddesc} |