diff options
Diffstat (limited to 'Doc')
| -rw-r--r-- | Doc/lib/libstdtypes.tex | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/Doc/lib/libstdtypes.tex b/Doc/lib/libstdtypes.tex index aabc9bf..87d5402 100644 --- a/Doc/lib/libstdtypes.tex +++ b/Doc/lib/libstdtypes.tex @@ -901,7 +901,7 @@ The following operations are defined on mutable sequence types (where \lineiii{\var{s}.reverse()} {reverses the items of \var{s} in place}{(6)} \lineiii{\var{s}.sort(\optional{\var{cmpfunc}})} - {sort the items of \var{s} in place}{(6), (7)} + {sort the items of \var{s} in place}{(6), (7), (8)} \end{tableiii} \indexiv{operations on}{mutable}{sequence}{types} \indexiii{operations on}{sequence}{types} @@ -947,10 +947,18 @@ Notes: the first argument is considered smaller than, equal to, or larger than the second argument. Note that this slows the sorting process down considerably; e.g. to sort a list in reverse order it is much - faster to use calls to the methods \method{sort()} and - \method{reverse()} than to use the built-in function - \function{sort()} with a comparison function that reverses the + faster to call method \method{sort()} followed by + \method{reverse()} than to use method + \method{sort()} with a comparison function that reverses the ordering of the elements. + +\item[(8)] Whether the \method{sort()} method is stable is not defined by + the language (a sort is stable if it guarantees not to change the + relative order of elements that compare equal). In the C + implementation of Python, sorts were stable only by accident through + Python 2.2. The C implementation of Python 2.3 introduced a stable + \method{sort()} method, but code that intends to be portable across + implementations and versions must not rely on stability. \end{description} |