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A comment on They don't even know the fundamentals. Parent comment

Re:They don't even know the fundamentals by Koshkin on Monday November 01, 2021 @08:43AM (#29065997)
This doesn’t sound correct to me. The original statement is, Let ϕ(x) be a property provable about objects x of type T. Then ϕ(y) should be true for objects y of type S where S is a subtype of T. Here, objects of a base class are replaced with objects of derived classes.
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Re:They don't even know the fundamentals by marcosdumay on Monday November 01, 2021 @11:20AM (#29067842)
> This doesn’t sound correct to me.

Yet the GP says exactly the same thing as you said. He just ignored that the property belongs to the base class.

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Re:They don't even know the fundamentals by kragen on Monday November 01, 2021 @12:42PM (#29069230)
The GP said "usable interchangeably", which is vague enough to admit a wide variety of interpretations, including the more rigorous one Koshkin posted.
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Re:They don't even know the fundamentals by marcosdumay on Tuesday November 02, 2021 @02:20PM (#29085312)
Yet he got unambiguously declared wrong...
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