# This code from
# PEP: 318
# Title: Decorators for Functions and Methods
# Version: 1.35
# Last-Modified: 2004/09/14 07:34:23
# Author: Kevin D. Smith, Jim Jewett, Skip Montanaro, Anthony Baxter
# This code fixes error in example 4:
# authors' code contains
# @accepts(int, (int,float))
# @returns((int,float))
# def func(arg1, arg2):
# return arg1 * arg2
#
# It should be:
# @returns((int,float))
# @accepts(int, (int,float))
# def func(arg1, arg2):
# return arg1 * arg2
# because of decorators are applied from bottom to up.
__rev_id__ = """$Id: Deco.py,v 1.4 2005/07/20 07:24:11 rvk Exp $"""
def accepts(*types):
#print types
def check_accepts(f):
assert len(types) == f.func_code.co_argcount
def new_f(*args, **kwds):
for (a, t) in zip(args, types):
assert isinstance(a, t), \
"arg %r does not match %s" % (a,t)
return f(*args, **kwds)
new_f.func_name = f.func_name
return new_f
return check_accepts
def returns(rtype):
def check_returns(f):
def new_f(*args, **kwds):
result = f(*args, **kwds)
assert isinstance(result, rtype), \
"return value %r does not match %s" % (result,rtype)
return result
new_f.func_name = f.func_name
return new_f
return check_returns
if __name__ == '__main__':
import types
@returns(types.NoneType)
@accepts(int, (int,float))
def func(arg1, arg2):
#return str(arg1 * arg2)
pass
func(1, 2)
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