# pocketpy: portable python 3.x interpreter
---
## This branch is in alpha stage. Old implementation was moved to v1.x branch.
---
pkpy is a lightweight(~15K LOC) Python 3.x interpreter for game scripting, written in C11.
It aims to be an alternative to lua for game scripting, with elegant syntax, powerful features and competitive performance.
pkpy is extremely easy to embed via a single header file `pocketpy.h`, without external dependencies.
Please see https://pocketpy.dev for details and try the following resources.
+ [Live Python Demo](https://pocketpy.dev/static/web/): Run Python code in your browser
## Supported Platforms
pkpy should work on any platform with a C11 compiler.
These platforms are officially tested.
+ Windows 64-bit
+ Linux 64-bit / 32-bit
+ macOS 64-bit
+ Android 64-bit / 32-bit
+ iOS 64-bit
+ Emscripten 32-bit
+ Raspberry Pi OS 64-bit
## Quick Start
You have two options to integrate pkpy into your project.
#### Use the single header file
Download the `pocketpy.h` on our [GitHub Release](https://github.com/pocketpy/pocketpy/releases) page.
And `#include` it in your project. The header can only be included once.
#### Use CMake
Clone the whole repository as a submodule into your project,
In your CMakelists.txt, add the following lines:
```cmake
add_subdirectory(pocketpy)
target_link_libraries( pocketpy)
```
See [CMakeLists.txt](https://github.com/pocketpy/pocketpy/blob/main/CMakeLists.txt) for details.
It is safe to use `main` branch in production if CI badge is green.
### Compile Flags
To compile it with your project, these flags must be set:
+ `--std=c11` flag must be set
+ For MSVC, `/utf-8` flag must be set
For amalgamated build, run `python amalgamate.py` to generate `pocketpy.c` and `pocketpy.h` in `amalgamated/` directory.
### Example
```c
#include "pocketpy.h"
#include
static bool int_add(int argc, py_Ref argv) {
PY_CHECK_ARGC(2);
PY_CHECK_ARG_TYPE(0, tp_int);
PY_CHECK_ARG_TYPE(1, tp_int);
py_i64 a = py_toint(py_arg(0));
py_i64 b = py_toint(py_arg(1));
py_newint(py_retval(), a + b);
return true;
}
int main() {
// Initialize pocketpy
py_initialize();
// Hello world!
bool ok = py_exec("print('Hello world!')", "", EXEC_MODE, NULL);
if(!ok) goto __ERROR;
// Create a list: [1, 2, 3]
py_Ref r0 = py_getreg(0);
py_newlistn(r0, 3);
py_newint(py_list_getitem(r0, 0), 1);
py_newint(py_list_getitem(r0, 1), 2);
py_newint(py_list_getitem(r0, 2), 3);
// Eval the sum of the list
py_Ref f_sum = py_getbuiltin(py_name("sum"));
py_push(f_sum);
py_pushnil();
py_push(r0);
ok = py_vectorcall(1, 0);
if(!ok) goto __ERROR;
printf("Sum of the list: %d\n", (int)py_toint(py_retval())); // 6
// Bind native `int_add` as a global variable
py_newnativefunc(r0, int_add);
py_setglobal(py_name("add"), r0);
// Call `add` in python
ok = py_exec("add(3, 7)", "", EVAL_MODE, NULL);
if(!ok) goto __ERROR;
py_i64 res = py_toint(py_retval());
printf("Sum of 2 variables: %d\n", (int)res); // 10
py_finalize();
return 0;
__ERROR:
py_printexc();
py_finalize();
return 1;
}
```
## Features
Check this [Cheatsheet](https://reference.pocketpy.dev/python.html)
for a quick overview of the supported features.
| Name | Example | Supported |
| --------------- | ------------------------------- | --------- |
| If Else | `if..else..elif` | ✅ |
| Loop | `for/while/break/continue` | ✅ |
| Function | `def f(x,*args,y=1):` | ✅ |
| Subclass | `class A(B):` | ✅ |
| List | `[1, 2, 'a']` | ✅ |
| ListComp | `[i for i in range(5)]` | ✅ |
| Slice | `a[1:2], a[:2], a[1:]` | ✅ |
| Tuple | `(1, 2, 'a')` | ✅ |
| Dict | `{'a': 1, 'b': 2}` | ✅ |
| F-String | `f'value is {x}'` | ✅ |
| Unpacking | `a, b = 1, 2` | ✅ |
| Star Unpacking | `a, *b = [1, 2, 3]` | ✅ |
| Exception | `raise/try..catch..finally` | ✅ |
| Dynamic Code | `eval()/exec()` | ✅ |
| Reflection | `hasattr()/getattr()/setattr()` | ✅ |
| Import | `import/from..import` | ✅ |
| Context Block | `with as :` | ✅ |
| Type Annotation | `def f(a:int, b:float=1)` | ✅ |
| Generator | `yield i` | ✅ |
| Decorator | `@cache` | ✅ |
## Performance
Currently, pkpy is as fast as cpython 3.9.
Performance results for cpython 3.9 are applicable to for pkpy.
See https://pocketpy.dev/performance/ for details.
And these are the results of the primes benchmark on Intel i5-12400F, WSL (Ubuntu 20.04 LTS), which *roughly* reflects the performance among c++, lua, pkpy and cpython.
| name | version | time | file |
| ---- | ---- | ---- | ---- |
| c++ | gnu++11 | `0.104s ■□□□□□□□□□□□□□□□` | [benchmarks/primes.cpp](https://github.com/pocketpy/pocketpy/blob/9481d653b60b81f4590a4d48f2be496f6962261e/benchmarks/primes.cpp) |
| lua | 5.3.3 | `1.576s ■■■■■■■■■□□□□□□□` | [benchmarks/primes.lua](https://github.com/pocketpy/pocketpy/blob/9481d653b60b81f4590a4d48f2be496f6962261e/benchmarks/primes.lua) |
| pkpy | 1.2.7 | `2.385s ■■■■■■■■■■■■■□□□` | [benchmarks/primes.py](https://github.com/pocketpy/pocketpy/blob/9481d653b60b81f4590a4d48f2be496f6962261e/benchmarks/primes.py) |
| cpython | 3.8.10 | `2.871s ■■■■■■■■■■■■■■■■` | [benchmarks/primes.py](https://github.com/pocketpy/pocketpy/blob/9481d653b60b81f4590a4d48f2be496f6962261e/benchmarks/primes.py) |
## Used By
| | Description |
|-----------------------------------------------------------------|--------------------------------------------------------------------------|
| [TIC-80](https://github.com/nesbox/TIC-80) | TIC-80 is a fantasy computer for making, playing and sharing tiny games. |
| [MiniPythonIDE](https://github.com/CU-Production/MiniPythonIDE) | A python ide base on pocketpy |
| [py-js](https://github.com/shakfu/py-js) | Python3 externals for Max / MSP |
| [crescent](https://github.com/chukobyte/crescent) | Crescent is a cross-platform 2D fighting and beat-em-up game engine. |
Submit a pull request to add your project here.
## Contribution
All kinds of contributions are welcome.
- Submit a Pull Request
- fix a bug
- add a new feature
- Open an Issue
- any suggestions
- any questions
If you find pkpy useful, consider star this repository (●'◡'●)
## Sponsor this project
You can sponsor this project via these ways.
+ [Github Sponsors](https://github.com/sponsors/blueloveTH)
+ [Buy me a coffee](https://www.buymeacoffee.com/blueloveth)
Your sponsorship will help us develop pkpy continuously.
## Reference
+ [cpython](https://github.com/python/cpython)
The official implementation of Python programming language.
+ [byterun](https://www.aosabook.org/en/500L/a-python-interpreter-written-in-python.html)
An excellent learning material. It illustrates how Python's virtual machine works.
## Star History
[](https://star-history.com/#blueloveth/pocketpy&Date)
## License
[MIT License](http://opensource.org/licenses/MIT)