There's an answer on Quora right now that claims, using theoretical computer science terminology that I'm only roughly versed in, that JavaScript is not Turing Complete. In short, he makes the claim that JavaScript is only a Pushdown Automaton, which seems on its face to be ludicrous. He also claims that JavaScript lacks the equivalent of a HALT instruction, which seems to my inexpert eyes to be even more of a stretch, and he makes a few side claims as well.

It almost feels like he's just trolling, but I fear that people will actually be convinced by this academic-sounding argument that JavaScript is somehow objectively limited compared to other languages. There are certainly issues with JavaScript, but it doesn't seem to me that the question of Turing Completeness is one of them.

I've posted my own answer to the original question, but I can't comment on his directly because, after a debate about some of his claims, he blocked me because I wouldn't re-read all of Turing's original paper on the topic. When you block a user on Quora it apparently hides all of their comments on your posts.

This does not bode well for rational debate, and I'm not asking for people to respond to him directly. If you do, please be respectful: He seems to have a hair-trigger for blocking users (I spoke with one other who was blocked) and reporting content he doesn't like (two such messages I'm aware of).

What I'm really asking for is a reality check: I don't have a graduate level CS degree, and my understanding of all of these topics is very superficial. Reading Turing's paper would probably require reading at least one book on how to understand the terminology and symbols used; I skimmed it, but wouldn't be able to fully grok it without much more study than seemed necessary, since every secondary reference I found that described what it meant agreed with my own understanding.

So am I completely wrong? If so I'm happy to withdraw my own answer. When I was debating with the Original Asker in another thread, it felt like he was changing his argument every time I pinned him down, and he refused to supply an example of an algorithm that can't be computed in JavaScript. But a feeling doesn't prove anything.

If you find any obvious mistakes in my own response, please let me know and I'll fix them (or you can "suggest edits" on Quora if that's easier for you). But the underlying question is bugging me. Does his argument have merit?