py2cpp

A Python to C++ compiler.

Install

pip install -e git+https://github.com/mugwort-rc/py2cpp.git#egg=py2cpp

Usage

Hello world

$ cat helloworld.py
def main() -> int:
    print("Hello World!")
    return 0

$ python -m py2cpp helloworld.py
// generate by py2cpp
// original source code: helloworld.py
#include "py2cpp/py2cpp.hpp"

int main() {
    std::cout << "Hello World!" << std::endl;
    return 0;
}

range function

$ cat range.py
def main() -> int:
    x = 0
    for i in range(100):
        x += i
    print(x)
    return 0

$ python -m py2cpp range.py
// generate by py2cpp
// original source code: range.py
#include "py2cpp/py2cpp.hpp"

int main() {
    x = 0;
    for (auto i : py2cpp::range(100)) {
        x += i;
    }
    std::cout << x << std::endl;
    return 0;
}

argument annotation

$ cat add.py
def add(x: float, y: float) -> float:
    return x + y

def main() -> int:
    print("2.0 + 3.0 =", add(2.0, 3.0))
    return 0

$ python -m py2cpp add.py
// generate by py2cpp
// original source code: add.py
#include "py2cpp/py2cpp.hpp"

double add(double x, double y) {
    return x + y;
}

int main() {
    std::cout << "2.0 + 3.0 =" << add(2.0, 3.0) << std::endl;
    return 0;
}

AST Node

https://docs.python.jp/3/library/ast.html

Supported

Modules

• Module

Statements

• FunctionDef
• ClassDef
• Return
• Assign
• AugAssign
• For
• While
• If
• Raise
• Expr
• Pass
• Break
• Continue

Expressions

• BoolOp
• BinOp
• UnaryOp
• Lambda
• IfExp
• Compare
• Call
• Num
• Str
• NameConstant
• Attribute
• Subscript
• Name
• Tuple
• Index
• arguments
• arg
• keyword

Unsupported yet

$ cat unsupported.py
try:
    raise Exception()
except:
    pass

$ python -m py2cpp unsupported.py
// generate by py2cpp
// original source code: unsupported.py
#include "py2cpp/py2cpp.hpp"

// UNSUPPORTED AST NODE: Try

Modules

• Interactive
• Expression
• Suite

Statements

• AsyncFunctionDef
• Delete
• AnnAssign
• AsyncFor
• With
• AsyncWith
• Try
• Assert
• Import
• ImportFrom
• Global
• Nonlocal
• attributes

Expressions

• Dict
• Set
• ListComp
• SetComp
• DictComp
• GeneratorExp
• Await
• Yield
• YieldFrom
• FormattedValue
• JoinedStr
• Bytes
• Ellipsis
• Constant
• Starred
• List
• attributes
• expr_context
• slice
• boolop
• operator
• unaryop
• cmpop
• comprehension
• excepthandler
• alias
• withitem