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authorFred Drake <fdrake@acm.org>2002-08-19 21:58:58 (GMT)
committerFred Drake <fdrake@acm.org>2002-08-19 21:58:58 (GMT)
commit017778332f7be58df770302a3ad7627faec2842c (patch)
treeefb0b1e3c2653d72ce6bb8c8b6e21fd063931ce0 /Doc
parent45ec02aed14685c353e55841b5acbc0dadee76f8 (diff)
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Extend some comments on the order of values in the returns from
dict.items/keys/values/iteritems/iterkeys/itervalues().
Diffstat (limited to 'Doc')
-rw-r--r--Doc/lib/libstdtypes.tex22
1 files changed, 14 insertions, 8 deletions
diff --git a/Doc/lib/libstdtypes.tex b/Doc/lib/libstdtypes.tex
index d3e0079..9f23cdf 100644
--- a/Doc/lib/libstdtypes.tex
+++ b/Doc/lib/libstdtypes.tex
@@ -1049,13 +1049,13 @@ arbitrary objects):
{(6)}
\lineiii{\var{a}.iteritems()}
{return an iterator over (\var{key}, \var{value}) pairs}
- {(2)}
+ {(2), (3)}
\lineiii{\var{a}.iterkeys()}
{return an iterator over the mapping's keys}
- {(2)}
+ {(2), (3)}
\lineiii{\var{a}.itervalues()}
{return an iterator over the mapping's values}
- {(2)}
+ {(2), (3)}
\end{tableiii}
\noindent
@@ -1067,11 +1067,17 @@ in the map.
\item[(2)] \versionadded{2.2}
\item[(3)] Keys and values are listed in random order. If
-\method{keys()} and \method{values()} are called with no intervening
-modifications to the dictionary, the two lists will directly
-correspond. This allows the creation of \code{(\var{value},
-\var{key})} pairs using \function{zip()}: \samp{pairs =
-zip(\var{a}.values(), \var{a}.keys())}.
+\method{items()}, \method{keys()}, \method{values()},
+\method{iteritems()}, \method{iterkeys()}, and \method{itervalues()}
+are called with no intervening modifications to the dictionary, the
+lists will directly correspond. This allows the creation of
+\code{(\var{value}, \var{key})} pairs using \function{zip()}:
+\samp{pairs = zip(\var{a}.values(), \var{a}.keys())}. The same
+relationship holds for the \method{iterkeys()} and
+\method{itervalues()} methods: \samp{pairs = zip(\var{a}.itervalues(),
+\var{a}.iterkeys())} provides the same value for \code{pairs}.
+Another way to create the same list is \samp{pairs = [(v, k) for (k,
+v) in \var{a}.iteritems()]}.
\item[(4)] Never raises an exception if \var{k} is not in the map,
instead it returns \var{x}. \var{x} is optional; when \var{x} is not