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55 | <H2><A NAME="SECTION007310000000000000000"></A><A NAME="attribute-references"></A> | |
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57 | 5.3.1 Attribute references | |
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59 | <a id='l2h-364' xml:id='l2h-364'></a> | |
60 | <P> | |
61 | An attribute reference is a primary followed by a period and a name: | |
62 | ||
63 | <P> | |
64 | <dl><dd class="grammar"> | |
65 | <div class="productions"> | |
66 | <table> | |
67 | <tr> | |
68 | <td><a id='tok-attributeref' xml:id='tok-attributeref'>attributeref</a></td> | |
69 | <td>::=</td> | |
70 | <td><a class='grammartoken' href="primaries.html#tok-primary">primary</a> "." <a class='grammartoken' href="identifiers.html#tok-identifier">identifier</a></td></tr> | |
71 | </table> | |
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73 | <a class="grammar-footer" | |
74 | href="grammar.txt" type="text/plain" | |
75 | >Download entire grammar as text.</a> | |
76 | </dd></dl> | |
77 | ||
78 | <P> | |
79 | The primary must evaluate to an object of a type that supports | |
80 | attribute references, e.g., a module, list, or an instance. This | |
81 | object is then asked to produce the attribute whose name is the | |
82 | identifier. If this attribute is not available, the exception | |
83 | <tt class="exception">AttributeError</tt><a id='l2h-365' xml:id='l2h-365'></a> is raised. | |
84 | Otherwise, the type and value of the object produced is determined by | |
85 | the object. Multiple evaluations of the same attribute reference may | |
86 | yield different objects. | |
87 | <a id='l2h-366' xml:id='l2h-366'></a><a id='l2h-367' xml:id='l2h-367'></a> | |
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