> Thank you! For this question, invoke indeed a good solution :)
>
> How about a more general case. For example, I already have a function foo
> foo(X::Int)=X+1
> in the environment.
>
> Then I want to overload foo to forbid negative input:
> function foo(X::Int)
> @assert(X>=0,"X should be a positive number.")
> invoke(foo,(Int,),X)#Here, I hope to call the original definition of
> foo.
> end
>
> However, invoke doesn't work as I expected in this case. Is there any other
> solution?
I don't think there is. There can only be one method for each signature
for one generic function. So above gets you into an infinite recursion.
> On Sunday, April 26, 2015 at 8:40:06 AM UTC+2, Sam L wrote:
>>
>> See ?invoke.
>>
>> display(X::Vector)=length(X)>10?print("Too long to show."):
>> invoke(display, (Any,), X)
>>
>> On Saturday, April 25, 2015 at 10:41:39 PM UTC-7, Jerry Xiong wrote:
>>>
>>> For example, if I want to overload the Base.display(::Vector) to repress
>>> the display when the vector is too long, I coded as below:
>>> julia> import Base.display
>>>
>>> julia> display(X::Vector)=length(X)>10?print("Too long to show."):Base.
>>> display(X)
>>> display (generic function with 17 methods)
>>>
>>> julia> display([1,2,3])
>>> ERROR: stack overflow
>>> in display at none:1 (repeats 39998 times)
>>>
>>> I want to call the original Base.display when the length of vector is
>>> less than 10, but it is became a dead recurring. Is there any way to do it?
>>>
>>
