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本文實例講述了python通過裝飾器檢查函數參數數據類型的方法。分享給大家供大家參考。具體分析如下：

這段代碼定義了一個python裝飾器，通過此裝飾器可以用來檢查指定函數的參數是否是指定的類型，在定義函數時加入此裝飾器可以非常清晰的檢測函數參數的類型，非常方便

	def accepts(exception,**types):

	    def check_accepts(f):

	        assert len(types) == f.func_code.co_argcount, \

	        'accept number of arguments not equal with function number of arguments in "%s"' % f.func_name

	        def new_f(*args, **kwds):

	            for i,v in enumerate(args):

	                if types.has_key(f.func_code.co_varnames[i]) and \

	                    not isinstance(v, types[f.func_code.co_varnames[i]]):

	                    raise exception("arg '%s'=%r does not match %s" % \

	                        (f.func_code.co_varnames[i],v,types[f.func_code.co_varnames[i]]))

	                    del types[f.func_code.co_varnames[i]]

	            for k,v in kwds.iteritems():

	                if types.has_key(k) and not isinstance(v, types[k]):

	                    raise exception("arg '%s'=%r does not match %s" % \

	                        (k,v,types[k]))

	            return f(*args, **kwds)

	        new_f.func_name = f.func_name

	        return new_f

	    return check_accepts

	def exmaple():

	    @accepts(Exception,a=int,b=list,c=(str,unicode))

	    def test(a,b=None,c=None)

	        print 'ok'

	    test(13,c=[],b='df')