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| 55 | <H1><A NAME="SECTION007500000000000000000"></A><A NAME="unary"></A> |
| 56 | <BR> |
| 57 | 5.5 Unary arithmetic operations |
| 58 | </H1> |
| 59 | <a id='l2h-408' xml:id='l2h-408'></a><a id='l2h-409' xml:id='l2h-409'></a> |
| 60 | <P> |
| 61 | All unary arithmetic (and bit-wise) operations have the same priority: |
| 62 | |
| 63 | <P> |
| 64 | <dl><dd class="grammar"> |
| 65 | <div class="productions"> |
| 66 | <table> |
| 67 | <tr> |
| 68 | <td><a id='tok-u_expr' xml:id='tok-u_expr'>u_expr</a></td> |
| 69 | <td>::=</td> |
| 70 | <td><a class='grammartoken' href="power.html#tok-power">power</a> | "-" <a class='grammartoken' href="unary.html#tok-u_expr">u_expr</a> |
| 71 | | "+" <a class='grammartoken' href="unary.html#tok-u_expr">u_expr</a> | "~" <a class='grammartoken' href="unary.html#tok-u_expr">u_expr</a></td></tr> |
| 72 | </table> |
| 73 | </div> |
| 74 | <a class="grammar-footer" |
| 75 | href="grammar.txt" type="text/plain" |
| 76 | >Download entire grammar as text.</a> |
| 77 | </dd></dl> |
| 78 | |
| 79 | <P> |
| 80 | The unary <code>-</code> (minus) operator yields the negation of its |
| 81 | numeric argument. |
| 82 | <a id='l2h-411' xml:id='l2h-411'></a> |
| 83 | |
| 84 | <P> |
| 85 | The unary <code>+</code> (plus) operator yields its numeric argument |
| 86 | unchanged. |
| 87 | <a id='l2h-412' xml:id='l2h-412'></a> |
| 88 | |
| 89 | <P> |
| 90 | The unary <code>~</code> (invert) operator yields the bit-wise inversion |
| 91 | of its plain or long integer argument. The bit-wise inversion of |
| 92 | <code>x</code> is defined as <code>-(x+1)</code>. It only applies to integral |
| 93 | numbers. |
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| 95 | |
| 96 | <P> |
| 97 | In all three cases, if the argument does not have the proper type, |
| 98 | a <tt class="exception">TypeError</tt> exception is raised. |
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| 136 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> |
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