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Comment by Sharlin | Hacker News Reader

Should be noted that this only works on a "statically typeable" subset of Python where every variable has a de facto static type inferred at the first assignment. For instance, the following valid Python code would output invalid C++:

  var = []
  var = 2

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Yes you would have to program in a subset of python. But type annotations are not always needed.

For the array I do a little hackery. You can define the array without an initial value in the container and I can guess the value type.

  arr = []
  arr.append(1)

it will spit out

  std::vector<decltype(1)> arr{};
  arr.push_back(1);

Well, you could always begin another scope with each assignment.

    auto var = // this type can't be inferred because it's not used
    {
      auto var = 2;
    }

I'm too exhausted to think why this may not be applicable.

Python:

    x = 2
    if stringy: x = '2'
    print x+x # 4 or 22???

C++:

    int x = 2;
    if(stringy) string x = "2";
    print x+x; // 4 (string x is out of scope)

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