Remove positional arg "func" from curry.__init__

AUTHORS.md

@@ -19,3 +19,5 @@ José Ricardo                                    [@josericardo](https://github.c
 Tom Prince                                      [@tomprince](https://github.com/tomprince)
 
 Bart van Merriënboer                            [@bartvm](https://github.com/bartvm)
+
+Nikolaos-Digenis Karagiannis                    [@digenis](https://github.com/digenis/)

toolz/functoolz.py

@@ -152,7 +152,10 @@ class curry(object):
         toolz.curried - namespace of curried functions
                         http://toolz.readthedocs.org/en/latest/curry.html
     """
-    def __init__(self, func, *args, **kwargs):
+    def __init__(self, *args, **kwargs):
+        if not args:
+            raise TypeError('__init__() takes at least 2 arguments (1 given)')
+        func, args = args[0], args[1:]
         if not callable(func):
             raise TypeError("Input must be callable")
 

toolz/tests/test_functoolz.py

@@ -1,3 +1,6 @@
+import platform
+
+
 from toolz.functoolz import (thread_first, thread_last, memoize, curry,
                              compose, pipe, complement, do, juxt)
 from toolz.functoolz import _num_required_args
@@ -161,6 +164,7 @@ def test_curry_simple():
     cmap = curry(map)
     assert list(cmap(inc)([1, 2, 3])) == [2, 3, 4]
 
+    assert raises(TypeError, lambda: curry())
     assert raises(TypeError, lambda: curry({1: 2}))
 
 
@@ -186,6 +190,16 @@ def g(a=1, b=10, c=0):
     assert cg(0) == 2  # pass "a" as arg, not kwarg
     assert raises(TypeError, lambda: cg(1, 2))  # pass "b" as arg AND kwarg
 
+    def h(x, func=int):
+        return func(x)
+
+    if platform.python_implementation() != 'PyPy'\
+            or platform.python_version_tuple()[0] != '3':  # Bug on PyPy3<2.5
+        # __init__ must not pick func as positional arg
+        assert curry(h)(0.0) == 0
+        assert curry(h)(func=str)(0.0) == '0.0'
+        assert curry(h, func=str)(0.0) == '0.0'
+
 
 def test_curry_passes_errors():
     @curry