Commit 932aaaa0 authored by Raymond Hettinger's avatar Raymond Hettinger

* Show the keyword argument form of dict().

* Note that dict works with the "in" keyword.
parent 7dbcf5f1
...@@ -2146,8 +2146,8 @@ value using a non-existent key. ...@@ -2146,8 +2146,8 @@ value using a non-existent key.
The \method{keys()} method of a dictionary object returns a list of all The \method{keys()} method of a dictionary object returns a list of all
the keys used in the dictionary, in arbitrary order (if you want it the keys used in the dictionary, in arbitrary order (if you want it
sorted, just apply the \method{sort()} method to the list of keys). To sorted, just apply the \method{sort()} method to the list of keys). To
check whether a single key is in the dictionary, use the check whether a single key is in the dictionary, either use the dictionary's
\method{has_key()} method of the dictionary. \method{has_key()} method or the \keyword{in} keyword.
Here is a small example using a dictionary: Here is a small example using a dictionary:
...@@ -2166,6 +2166,8 @@ Here is a small example using a dictionary: ...@@ -2166,6 +2166,8 @@ Here is a small example using a dictionary:
['guido', 'irv', 'jack'] ['guido', 'irv', 'jack']
>>> tel.has_key('guido') >>> tel.has_key('guido')
True True
>>> 'guido' in tel
True
\end{verbatim} \end{verbatim}
The \function{dict()} constructor builds dictionaries directly from The \function{dict()} constructor builds dictionaries directly from
...@@ -2183,6 +2185,14 @@ Later in the tutorial, we will learn about Generator Expressions ...@@ -2183,6 +2185,14 @@ Later in the tutorial, we will learn about Generator Expressions
which are even better suited for the task of supplying key-values pairs to which are even better suited for the task of supplying key-values pairs to
the \function{dict()} constructor. the \function{dict()} constructor.
When the keys are simple strings, it is sometimes easier to specify
pairs using keyword arguments:
\begin{verbatim}
>>> dict(sape=4139, guido=4127, jack=4098)
{'sape': 4139, 'jack': 4098, 'guido': 4127}
\end{verbatim}
\section{Looping Techniques \label{loopidioms}} \section{Looping Techniques \label{loopidioms}}
......
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