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diff --git a/libs/python/doc/v2/exec.html b/libs/python/doc/v2/exec.html new file mode 100644 index 000000000..83d2c9b89 --- /dev/null +++ b/libs/python/doc/v2/exec.html @@ -0,0 +1,163 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> + +<!-- Copyright David Abrahams 2006. Distributed under the Boost --> +<!-- Software License, Version 1.0. (See accompanying --> +<!-- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) --> +<html> + <head> + <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> + <link rel="stylesheet" type="text/css" href="../boost.css"> + + <title>Boost.Python - <boost/python/exec.hpp></title> + </head> + + <body> + <table border="0" cellpadding="7" cellspacing="0" width="100%" summary= + "header"> + <tr> + <td valign="top" width="300"> + <h3><a href="../../../../index.htm"><img height="86" width="277" + alt="C++ Boost" src="../../../../boost.png" border="0"></a></h3> + </td> + + <td valign="top"> + <h1 align="center"><a href="../index.html">Boost.Python</a></h1> + + <h2 align="center">Header <boost/python/exec.hpp></h2> + </td> + </tr> + </table> + <hr> + + <h2>Contents</h2> + + <dl class="page-index"> + <dt><a href="#introduction">Introduction</a></dt> + + <dt><a href="#functions">Functions</a></dt> + + <dd> + <dl class="page-index"> + <dt><a href="#eval-spec"><code>eval</code></a></dt> + <dt><a href="#exec-spec"><code>exec</code></a></dt> + <dt><a href="#exec_file-spec"><code>exec_file</code></a></dt> + </dl> + </dd> + <dt><a href="#examples">Examples</a></dt> + </dl> + <hr> + + <h2><a name="introduction"></a>Introduction</h2> + + <p>Exposes a mechanism for embedding the python interpreter into C++ code.</p> + + <h2><a name="functions"></a>Functions</h2> + + <h3><a name="eval-spec"></a><code>eval</code></h3> + <pre> +object eval(str expression, + object globals = object(), + object locals = object()); + </pre> + <dl class="function-semantics"> + <dt><b>Effects:</b> + Evaluate Python expression from <code>expression</code> in the context + specified by the dictionaries <code>globals</code> and <code>locals</code>. + </dt> + <dt><b>Returns:</b> + An instance of <a href="object.html#object-spec">object</a> + which holds the value of the expression. + </dt> + </dl> + + <h3><a name="exec-spec"></a><code>exec</code></h3> + <pre> +object exec(str code, + object globals = object(), + object locals = object()); + </pre> + <dl class="function-semantics"> + <dt><b>Effects:</b> + Execute Python source code from <code>code</code> in the context + specified by the dictionaries <code>globals</code> and <code>locals</code>. + </dt> + <dt><b>Returns:</b> + An instance of <a href="object.html#object-spec">object</a> + which holds the result of executing the code. + </dt> + </dl> + + <h3><a name="exec_file-spec"></a><code>exec_file</code></h3> + <pre> +object exec_file(str filename, + object globals = object(), + object locals = object()); + </pre> + <dl class="function-semantics"> + <dt><b>Effects:</b> + Execute Python source code from the file named by <code>filename</code> + in the context specified by the dictionaries <code>globals</code> and + <code>locals</code>. + </dt> + <dt><b>Returns:</b> + An instance of <a href="object.html#object-spec">object</a> + which holds the result of executing the code. + </dt> + </dl> + + <h2><a name="examples"></a>Examples</h2> + + <para>The following example demonstrates the use of <function>import</function> + and <function>exec</function> to define a function in python, and later call + it from within C++.</para> + +<pre> +#include <iostream> +#include <string> + +using namespace boost::python; + +void greet() +{ + // Retrieve the main module. + object main = import("__main__"); + + // Retrieve the main module's namespace + object global(main.attr("__dict__")); + + // Define greet function in Python. + object result = exec( + "def greet(): \n" + " return 'Hello from Python!' \n", + global, global); + + // Create a reference to it. + object greet = global["greet"]; + + // Call it. + std::string message = extract<std::string>(greet()); + std::cout << message << std::endl; +} +</pre> + + <para>Instead of embedding the python script into a string, + we could also store it in an a file...</para> + +<pre> +def greet(): + return 'Hello from Python!' +</pre> + <para>... and execute that instead.</para> +<pre> + // ... + // Load the greet function from a file. + object result = exec_file(script, global, global); + // ... +} +</pre> + <p>Revised 01 November, 2005</p> + + <p><i>© Copyright Stefan Seefeld 2005.</i></p> + </body> +</html> + |