statically

Compiles a function or class with Cython. Use annotations for static type declarations.

Python 3 is required.

To compile, you must decorate the function or class with typed. Example:

import cython
import statically

@statically.typed
def func():
    # Cython types are evaluated as for cdef declarations
    x: cython.int               # cdef int x
    y: cython.double = 0.57721  # cdef double y = 0.57721
    z: cython.float  = 0.57721  # cdef float z  = 0.57721

    # Python types shadow Cython types for compatibility reasons
    a: float = 0.54321          # cdef double a = 0.54321
    b: int = 5                  # cdef object b = 5
    c: long = 6                 # cdef object c = 6

@statically.typed
class A:
    a: cython.int
    b: cython.int
    def __init__(self, b=0):
        self.a = 3
        self.b = b

Python 3.5 or less supports type hints in the parameters but not in the body of the code. Read the next case:

@statically.typed
def sum_powers(x: cython.int):
    return sum([x**n for n in range(1, x + 1)])

Works, but provides just a 5% increase in speed over the Python equivalent because the n variable is not annotated. In this case you can declare the type of the variable in the parameter with a default value.

@statically.typed
def sum_powers(x: cython.int, n: cython.int = 0):
    return sum([x**n for n in range(1, x + 1)])

For this function I got more than 1,400% speed increase.

Installation

$ pip install git+https://github.com/AlanCristhian/statically.git

Caveats

• Async generators are not supported.
• In contexts that doesn't have file - IDLE or REPL - will fallback to normal Python code. Works fine with IPython shell.

Contribute

I am not a native english speaker, so you can help me with the documentation. Also I am not convinced about the module name. The typed decorator can compile functions or classes without type declarations.

Feel free to send me a pull request or open an issue.