@@ -439,6 +439,11 @@ \section{Built-in Functions \label{built-in-funcs}}
439439 is always a list. If \var {function} is \code {None}, the identity
440440 function is assumed, that is, all elements of \var {list} that are false
441441 (zero or empty) are removed.
442+
443+ Note that \code {filter(function, list)} equals
444+ \code {[item for item in list if function(item)]} if function is not
445+ \code {None} and \code {[item for item in list if item]} if function is
446+ None.
442447\end {funcdesc }
443448
444449\begin {funcdesc }{float}{x}
@@ -537,9 +542,8 @@ \section{Built-in Functions \label{built-in-funcs}}
537542\begin {funcdesc }{int}{x\optional {, radix}}
538543 Convert a string or number to a plain integer. If the argument is a
539544 string, it must contain a possibly signed decimal number
540- representable as a Python integer, possibly embedded in whitespace;
541- this behaves identical to \code {string.atoi(\var {x}\optional {,
542- \var {radix}})}. The \var {radix} parameter gives the base for the
545+ representable as a Python integer, possibly embedded in whitespace.
546+ The \var {radix} parameter gives the base for the
543547 conversion and may be any integer in the range [2, 36], or zero. If
544548 \var {radix} is zero, the proper radix is guessed based on the
545549 contents of string; the interpretation is the same as for integer
@@ -904,6 +908,7 @@ \section{Built-in Functions \label{built-in-funcs}}
904908 The \var {sequence}'s items are normally numbers, and are not allowed
905909 to be strings. The fast, correct way to concatenate sequence of
906910 strings is by calling \code {''.join(\var {sequence})}.
911+ Note that \code {sum(range(n), m)} equals \code {reduce(operator.add, range(n), m)}
907912 \versionadded {2.3}
908913\end {funcdesc }
909914
0 commit comments