mirainc / python-typesafe

Runtime type-checking for Python 2.7

python-typesafe

Runtime type-checking for Python 2.7. Add decorators to your functions and properties to support runtime type safety of arguments and return types.

Usage

@types(x=str, returns=str)
def greet(x):
  return 'Hello ' + x

greet('user!')  # >>> Hello user!
greet(42)  # >>> x (42) is not type <type 'str'>

# Types
Any  # represents any type; ignored by checker
Class  # represents any type; analogous to types.TypeType

Optional  # optional type; allows for given type or None value
opt(str)  # optional type alias with a type value of str

# Properties
class TypesafeClass(object):
  def __init__(self):
    self._x = ''
    add_property(self, 'x', str)

instance = TypesafeClass()
instance.x  # >>> ''

flake8 Integration

def greet(x):
  return 'Hello ' + x

$ flake8 greet.py
greet.py:1:1: T000 function 'greet' does not have a type declaration

Installation

$ pip install git+git://github.com/mirainc/python-typesafe.git@v0.3

# in requirements.txt
-e git://github.com/mirainc/python-typesafe.git@v0.3#egg=typesafe