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You don't need a "looping construct" to be able to perform looping. GOTO is not a looping construct, but with it you can perform looping.

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For the purposes of this discussion, GOTO is a looping construct, because it does allow looping (that is, potentially running forever). As I understand it, the SVG sample does not demonstrate looping, and the parent is saying that SVG does not allow it as far as they know.

To be fair, for Turing completeness, "looping constructs" are not actually necessary. None of the "foundational" computational models (Turing machines, lambda calculus, Post tag systems, Magic the Gathering, ...) has any kind of "looping construct".

It may not even be enough: the most basic looping construct (i.e. a bounded for-loop) is primitive recursive, but not Turing complete. You couldn't implement the Ackermann function without more sophisticated tools.

Lambda calculate has a looping construct, recursion. You can make any loop with recursion, just like you can make any loop with goto. SVG appears to have neither of these things.

What is the difference? The point is to be able to take a transition back to an earlier state.

It's just a jump that can be used as a loop.

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