Python——函数重载

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Python不支持函数重载,但是Python3提供了一个装饰器@singledispatch,用于定义一个泛型函数

@singledispath装饰器

普通函数中使用

  • 示例代码
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    from functools import singledispatch
    from collections import  abc
    @singledispatch
    def show(obj):
        print (obj, type(obj), "obj")
     
    #参数字符串
    @show.register(str)
    def _(text):
        print (text, type(text), "str")
     
    #参数int
    @show.register(int)
    def _(n):
        print (n, type(n), "int")
     
     
    #参数元祖或者字典均可
    @show.register(tuple)
    @show.register(dict)
    def _(tup_dic):
        print (tup_dic, type(tup_dic), "tuple or dict")
     
    show(1)
    show("xx")
    show([1])
    show((1,2,3))
    show({"a":"b"})

    # Output:
    1 <class 'int'> int
    xx <class 'str'> str
    [1] <class 'list'> obj
    (1, 2, 3) <class 'tuple'> tuple or dict
    {'a': 'b'} <class 'dict'> tuple or dict

类中使用

  • 示例代码:
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    from functools import singledispatch
    class abs:
        def type(self,args):
            ""

    class Person(abs):

        @singledispatch
        def type(self,args):
            super().type("",args)
            print("我可以接受%s类型的参数%s"%(type(args),args))

        @type.register(str)
        def _(text):
            print("str",text)

        @type.register(tuple)
        def _(text):
            print("tuple", text)

        @type.register(list)
        @type.register(dict)
        def _(text):
            print("list or dict", text)

    Person.type("safly")
    Person.type((1,2,3))
    Person.type([1,2,3])
    Person.type({"a":1})
    Person.type(Person,True)

    # Output:
    str safly
    tuple (1, 2, 3)
    list or dict [1, 2, 3]
    list or dict {'a': 1}
    我可以接受<class 'bool'>类型的参数True