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Python Shell I / O Control

I need to evaluate (millions) of Python expressions, for example. (int(a) >> 8 == 4) and b in my OCaml program. There is pycaml, but I could not get it to work.

So, I turned to another idea: directly control the input / output of the Python interpreter.

Ideally, I would like to intercept as the input / output of the interpreter itself. By sending to the interpreter a = 3 b = 5 a > b, I could get the result Falseas if I had done it using the keyboard.

>>> a = 3
>>> b = 5
>>> a > b
False
>>>

However, my code does not work as expected (while the same code worked for some interactive program)

let (readme, writeme) = Unix.open_process "python -u";; 
let _ = output_string writeme "3 + 5\n" in
let _ = flush writeme in 
let result = input_line readme in
print_endline result;;

3 + 5\n print 3\n, input_line. ? , . , .

+3
2

( python o'caml), , python, eval, / / . eval.

+3

:

$ python -c 'a = 3; b = 5; print a > b'
False

?

, . , , 200 a = 3; b = 5; print a > b; - .

+2

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