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Comment by sxcurry | Hacker News Reader

Technically, UTC is a time standard, and GMT is a time zone, so the two, although equal, are not really the same thing. Also, you can set your iPhone to UTC in the World Clock, which I do as an amateur astronomer.

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I thought UTC the same, doesn't that mean that GMT+0 is essentially wrong? I thought GMT was essentially UTC+0, and all other time zones (ignoring DST) are defined as offsets to UTC, not GMT.

Think of it as two pointers referencing the same data:

    Time* UTC = Time(0);
    Time* GMT = *UTC;

    *UTC == *GMT; // True
    UTC == GMT; // False

Your example with pointers actually wouldn't compile, and I think the analogy you are trying to make is not accurate. On the second line you are assigning the target address of `GMT` to be the value pointed to by UTC. In other words you are trying to assign a value of type "Time" to an object to type "Pointer-to-Time".

If, however you meant for that line to be: Time *GMT = UTC;

it would compile fine, but then your second comparison would evaluate to true, and the whole analogy be rather pointless.

What I meant was to have them both point to the same data, but be different objects.

Sure, C wouldn't work that way, but it's just supposed to be pseudocode anyway.

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