Fun with Python decorators

gistfile1.py

"""
    Created on 2012-02-03
    @author: jldupont
    
    @pattern(int, str, [], "p1>p2")
    
    
    @patterned
    def function_name(p1, p2, p3):
    
    @pattern()
    def function_name(p1, p2):
        pass
        
    @pattern()
    def function_name(p1, p2, p3):
        pass
        
    @default 
    def function_name(p1, p2, p3):
        pass

"""
from functools import wraps


def patterned(f):
    @wraps(f)
    def wrapper(*pa, **ka):
        return f(*pa, **ka)
    
    ps=globals().get("__PATTERNED__", {})
    ps[f.__name__]=[]    
    globals()['__PATTERNED__']=ps
    return wrapper

class pattern(object):
    def __init__(self, *ps):
        self.ps=ps
        print "__init__ / ps: ", ps
        
    def __call__(self, f, *cpa):
        print "__call__ / f: ",f
        print "__call__/ cpa: ", cpa
        
        def wrapped_f(*pa):
            print "wrapped_f/pa: ", pa
            return f(*pa)
    
        return wrapped_f
    
@patterned
def f1(p1, p2):
    pass
    
@pattern(int, int)
def f1_p1(p1, p2):
    print "f1_p1: ", p1, p2
    
print "---------------"
    
@pattern
def f1_p2(p1, p2):
    print "f1_p2: ", p1, p2
    
    
print "++++++++++++++++++++"

f1_p1(1, 2)

print "++++++++++++++++++++"

f1_p2(3, 4)

"""
__init__ / ps:  (<type 'int'>, <type 'int'>)
__call__ / f:  <function f1_p1 at 0x7f559a5192a8>
__call__/ cpa:  ()
---------------
__init__ / ps:  (<function f1_p2 at 0x7f559a519398>,)
++++++++++++++++++++
wrapped_f/pa:  (1, 2)
f1_p1:  1 2
++++++++++++++++++++
__call__ / f:  3
__call__/ cpa:  (4,)
"""


if __name__=="__main__":
    import doctest
    doctest.testmod()