added exec functions

example/example18.cpp

@@ -0,0 +1,120 @@
+/*
+    example/example18.cpp -- Usage of exec, eval etc.
+
+    Copyright (c) 2016 Klemens D. Morgenstern
+
+    All rights reserved. Use of this source code is governed by a
+    BSD-style license that can be found in the LICENSE file.
+*/
+
+
+#include <pybind11/exec.h>
+#include "example.h"
+
+void example18() {
+    py::module main_module = py::module::import("__main__");
+    py::object main_namespace = main_module.attr("__dict__");
+
+    bool executed = false;
+
+    main_module.def("call_test", [&]()-> int {executed = true; return 42;});
+
+    cout << "exec test" << endl;
+
+    py::exec(
+            "print('Hello World!');\n"
+            "x = call_test();",
+                          main_namespace);
+
+    if (executed)
+        cout << "exec passed" << endl;
+    else {
+        cout << "exec failed" << endl;
+    }
+
+    cout << "eval test" << endl;
+
+    py::object val = py::eval("x", main_namespace);
+
+    if (val.cast<int>() == 42)
+        cout << "eval passed" << endl;
+    else {
+        cout << "eval failed" << endl;
+    }
+
+
+    executed = false;
+    cout << "exec_statement test" << endl;
+
+    py::exec_statement("y = call_test();", main_namespace);
+
+
+    if (executed)
+        cout << "exec_statement passed" << endl;
+    else {
+        cout << "exec_statement failed" << endl;
+    }
+
+    cout << "exec_file test" << endl;
+
+    int val_out;
+    main_module.def("call_test2", [&](int value) {val_out = value;});
+
+
+    py::exec_file("example18_call.py", main_namespace);
+
+    if (val_out == 42)
+        cout << "exec_file passed" << endl;
+    else {
+        cout << "exec_file failed" << endl;
+    }
+
+    executed = false;
+    cout << "exec failure test" << endl;
+    try {
+    	py::exec("non-sense code ...");
+    }
+    catch (py::error_already_set & err) {
+    	executed = true;
+    }
+    if (executed)
+        cout << "exec failure test passed" << endl;
+    else {
+        cout << "exec failure test failed" << endl;
+    }
+
+
+    executed = false;
+    cout << "exec_file failure test" << endl;
+    try {
+    	py::exec_file("none-existing file");
+    }
+    catch (std::invalid_argument & err) {
+    	executed = true;
+    }
+    if (executed)
+        cout << "exec_file failure test passed" << endl;
+    else {
+        cout << "exec_file failure test failed" << endl;
+    }
+
+    executed = false;
+    cout << "eval failure test" << endl;
+    try {
+    	py::eval("print('dummy')");
+    }
+    catch (py::error_already_set & err) {
+    	executed = true;
+    }
+    if (executed)
+        cout << "eval failure test passed" << endl;
+    else {
+        cout << "eval failure test failed" << endl;
+    }
+}
+
+void init_ex18(py::module & m) {
+	m.def("example18", &example18);
+}
+
+