Commit | Line | Data |
---|---|---|
86530b38 AT |
1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
2 | <html> | |
3 | <head> | |
4 | <link rel="STYLESHEET" href="lib.css" type='text/css' /> | |
5 | <link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" /> | |
6 | <link rel='start' href='../index.html' title='Python Documentation Index' /> | |
7 | <link rel="first" href="lib.html" title='Python Library Reference' /> | |
8 | <link rel='contents' href='contents.html' title="Contents" /> | |
9 | <link rel='index' href='genindex.html' title='Index' /> | |
10 | <link rel='last' href='about.html' title='About this document...' /> | |
11 | <link rel='help' href='about.html' title='About this document...' /> | |
12 | <link rel="next" href="node770.html" /> | |
13 | <link rel="prev" href="node768.html" /> | |
14 | <link rel="parent" href="module-parser.html" /> | |
15 | <link rel="next" href="node770.html" /> | |
16 | <meta name='aesop' content='information' /> | |
17 | <title>18.1.3 Queries on AST Objects </title> | |
18 | </head> | |
19 | <body> | |
20 | <DIV CLASS="navigation"> | |
21 | <div id='top-navigation-panel' xml:id='top-navigation-panel'> | |
22 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
23 | <tr> | |
24 | <td class='online-navigation'><a rel="prev" title="18.1.2 Converting AST Objects" | |
25 | href="node768.html"><img src='../icons/previous.png' | |
26 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
27 | <td class='online-navigation'><a rel="parent" title="18.1 parser " | |
28 | href="module-parser.html"><img src='../icons/up.png' | |
29 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
30 | <td class='online-navigation'><a rel="next" title="18.1.4 Exceptions and Error" | |
31 | href="node770.html"><img src='../icons/next.png' | |
32 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
33 | <td align="center" width="100%">Python Library Reference</td> | |
34 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
35 | href="contents.html"><img src='../icons/contents.png' | |
36 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
37 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
38 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
39 | <td class='online-navigation'><a rel="index" title="Index" | |
40 | href="genindex.html"><img src='../icons/index.png' | |
41 | border='0' height='32' alt='Index' width='32' /></A></td> | |
42 | </tr></table> | |
43 | <div class='online-navigation'> | |
44 | <b class="navlabel">Previous:</b> | |
45 | <a class="sectref" rel="prev" href="node768.html">18.1.2 Converting AST Objects</A> | |
46 | <b class="navlabel">Up:</b> | |
47 | <a class="sectref" rel="parent" href="module-parser.html">18.1 parser </A> | |
48 | <b class="navlabel">Next:</b> | |
49 | <a class="sectref" rel="next" href="node770.html">18.1.4 Exceptions and Error</A> | |
50 | </div> | |
51 | <hr /></div> | |
52 | </DIV> | |
53 | <!--End of Navigation Panel--> | |
54 | ||
55 | <H2><A NAME="SECTION0020130000000000000000"></A><A NAME="Querying_ASTs"></A> | |
56 | <BR> | |
57 | 18.1.3 Queries on AST Objects | |
58 | </H2> | |
59 | ||
60 | <P> | |
61 | Two functions are provided which allow an application to determine if | |
62 | an AST was created as an expression or a suite. Neither of these | |
63 | functions can be used to determine if an AST was created from source | |
64 | code via <tt class="function">expr()</tt> or <tt class="function">suite()</tt> or from a parse tree | |
65 | via <tt class="function">sequence2ast()</tt>. | |
66 | ||
67 | <P> | |
68 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> | |
69 | <td><nobr><b><tt id='l2h-4946' xml:id='l2h-4946' class="function">isexpr</tt></b>(</nobr></td> | |
70 | <td><var>ast</var>)</td></tr></table></dt> | |
71 | <dd> | |
72 | When <var>ast</var> represents an <code>'eval'</code> form, this function | |
73 | returns true, otherwise it returns false. This is useful, since code | |
74 | objects normally cannot be queried for this information using existing | |
75 | built-in functions. Note that the code objects created by | |
76 | <tt class="function">compileast()</tt> cannot be queried like this either, and are | |
77 | identical to those created by the built-in | |
78 | <tt class="function">compile()</tt><a id='l2h-4947' xml:id='l2h-4947'></a> function. | |
79 | </dl> | |
80 | ||
81 | <P> | |
82 | <dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline"> | |
83 | <td><nobr><b><tt id='l2h-4948' xml:id='l2h-4948' class="function">issuite</tt></b>(</nobr></td> | |
84 | <td><var>ast</var>)</td></tr></table></dt> | |
85 | <dd> | |
86 | This function mirrors <tt class="function">isexpr()</tt> in that it reports whether an | |
87 | AST object represents an <code>'exec'</code> form, commonly known as a | |
88 | ``suite.'' It is not safe to assume that this function is equivalent | |
89 | to "<tt class="samp">not isexpr(<var>ast</var>)</tt>", as additional syntactic fragments may | |
90 | be supported in the future. | |
91 | </dl> | |
92 | ||
93 | <P> | |
94 | ||
95 | <DIV CLASS="navigation"> | |
96 | <div class='online-navigation'> | |
97 | <p></p><hr /> | |
98 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
99 | <tr> | |
100 | <td class='online-navigation'><a rel="prev" title="18.1.2 Converting AST Objects" | |
101 | href="node768.html"><img src='../icons/previous.png' | |
102 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
103 | <td class='online-navigation'><a rel="parent" title="18.1 parser " | |
104 | href="module-parser.html"><img src='../icons/up.png' | |
105 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
106 | <td class='online-navigation'><a rel="next" title="18.1.4 Exceptions and Error" | |
107 | href="node770.html"><img src='../icons/next.png' | |
108 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
109 | <td align="center" width="100%">Python Library Reference</td> | |
110 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
111 | href="contents.html"><img src='../icons/contents.png' | |
112 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
113 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
114 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
115 | <td class='online-navigation'><a rel="index" title="Index" | |
116 | href="genindex.html"><img src='../icons/index.png' | |
117 | border='0' height='32' alt='Index' width='32' /></A></td> | |
118 | </tr></table> | |
119 | <div class='online-navigation'> | |
120 | <b class="navlabel">Previous:</b> | |
121 | <a class="sectref" rel="prev" href="node768.html">18.1.2 Converting AST Objects</A> | |
122 | <b class="navlabel">Up:</b> | |
123 | <a class="sectref" rel="parent" href="module-parser.html">18.1 parser </A> | |
124 | <b class="navlabel">Next:</b> | |
125 | <a class="sectref" rel="next" href="node770.html">18.1.4 Exceptions and Error</A> | |
126 | </div> | |
127 | </div> | |
128 | <hr /> | |
129 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> | |
130 | </DIV> | |
131 | <!--End of Navigation Panel--> | |
132 | <ADDRESS> | |
133 | See <i><a href="about.html">About this document...</a></i> for information on suggesting changes. | |
134 | </ADDRESS> | |
135 | </BODY> | |
136 | </HTML> |