Drop Python 3.4 support

.travis.yml

@@ -1,7 +1,6 @@
 dist: xenial
 language: python
 python:
-  - 3.4
   - 3.5
   - 3.6
   - 3.7

polypie.py

@@ -1,6 +1,6 @@
 from collections import OrderedDict
 from functools import update_wrapper
-from inspect import Parameter, signature
+from inspect import signature
 from typing import get_type_hints
 
 from typeguard import check_argument_types, _CallMemo
@@ -18,21 +18,6 @@ class PolypieException(Exception):
     pass
 
 
-class HashableParameter(Parameter):
-
-    def __hash__(self):
-        return hash((self.name, self.kind, self.default, self.annotation))
-
-    @classmethod
-    def from_parameter(cls, parameter):
-        return cls(
-            name=parameter.name,
-            kind=parameter.kind,
-            default=parameter.default,
-            annotation=parameter.annotation
-        )
-
-
 def _call_func(func_key, args=None, kwargs=None):
     args = args or ()
     kwargs = kwargs or {}
@@ -60,8 +45,7 @@ def polymorphic(func):
     global _registry
     func_key = func.__module__ + '.' + func.__qualname__
     parameters = signature(func).parameters
-    parameters_tuple = tuple(
-        HashableParameter.from_parameter(p) for p in parameters.values())
+    parameters_tuple = tuple(parameters.values())
     if func_key not in _registry:
         def dispatcher(*args, **kwargs):
             return _call_func(func_key, args, kwargs)

setup.py

@@ -23,6 +23,7 @@
     version=version,
     py_modules=['polypie'],
     install_requires=['typeguard'],
+    python_requires='>=3.5',
     license='BSD License',
     description='Python polymorphic function declaration with obvious syntax',
     long_description=long_description,
@@ -34,7 +35,6 @@
         'License :: OSI Approved :: BSD License',
         'Operating System :: OS Independent',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py34,py35,py36,py37,flake8
+envlist = py35,py36,py37,flake8
 
 [testenv]
 deps = pytest-cov