--- icon: dot label: 'Installation' order: 100 --- Download the `pocketpy.h` on our [GitHub Release](https://github.com/blueloveTH/pocketpy/releases) page. And `#include` it in your project. ### Compile flags To compile it with your project, these flags must be set: + `--std=c++17` flag must be set + Exception must be enabled + RTTI is not required !!! For maximum performance, we recommend to use `clang++` with `-O2` flag. !!! ### Example ```cpp #include "pocketpy.h" using namespace pkpy; int main(){ // Create a virtual machine VM* vm = new VM(); // Hello world! vm->exec("print('Hello world!')", "main.py", EXEC_MODE); // Create a list vm->exec("a = [1, 2, 3]", "main.py", EXEC_MODE); // Eval the sum of the list PyObject* result = vm->exec("sum(a)", "", EVAL_MODE); std::cout << CAST(int, result); // 6 return 0; } ``` ### Overview pkpy's C++ interfaces are organized in an object-oriented way. All classes are located in `pkpy` namespace. The most important class is the `VM` class. A `VM` instance is a python virtual machine which holds all necessary runtime states, including callstacks, modules, variables, etc. You need to use the C++ `new` operator to create a `VM` instance. ```cpp VM* vm = new VM(); ``` The constructor can take 1 extra parameters. #### `VM(bool enable_os=true)` + `enable_os`, whether to enable OS-related features or not. This setting controls the availability of some priviledged modules such os `io` and `os` as well as builtin function `open`. When you are done with the `VM` instance, you need to use the C++ `delete` operator to free the memory. ```cpp delete vm; ```