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<title>5.2.6 Dictionary displays</title>
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<H2><A NAME="SECTION007260000000000000000"></A><A NAME="dict"></A>
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5.2.6 Dictionary displays
</H2>
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A dictionary display is a possibly empty series of key/datum pairs
enclosed in curly braces:
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    <td><a id='tok-dict_display' xml:id='tok-dict_display'>dict_display</a></td>
    <td>::=</td>
    <td>"{" [<a class='grammartoken' href="dict.html#tok-key_datum_list">key_datum_list</a>] "}"</td></tr>
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    <td><a id='tok-key_datum_list' xml:id='tok-key_datum_list'>key_datum_list</a></td>
    <td>::=</td>
    <td><a class='grammartoken' href="dict.html#tok-key_datum">key_datum</a> ("," <a class='grammartoken' href="dict.html#tok-key_datum">key_datum</a>)* [","]</td></tr>
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<a class="grammar-footer"
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  >Download entire grammar as text.</a>
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A dictionary display yields a new dictionary object.
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The key/datum pairs are evaluated from left to right to define the
entries of the dictionary: each key object is used as a key into the
dictionary to store the corresponding datum.

<P>
Restrictions on the types of the key values are listed earlier in
section <A href="types.html#types">3.2</A>.  (To summarize, the key type should be hashable,
which excludes all mutable objects.)  Clashes between duplicate keys
are not detected; the last datum (textually rightmost in the display)
stored for a given key value prevails.
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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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