Comment by domnodom | Hacker News Reader

Comment by domnodom | Hacker News Reader

Not all browsers had or have a DOM, and some didn’t until later versions.

Early browsers without DOMs (with initial release date): WorldWideWeb (Nexus) (Dec 1990), Erwise (Apr 1992), ViolaWWW (May 1992), Lynx (1992), NCSA Mosaic 1.0 (Apr 1993), Netscape 1.0 (Dec 1994), and IE 1.0 (Aug 1995).

Note: Lynx remains a non-DOM browser by design.

AOL 1.0–2.0 (1994–1995) used the AOLPress engine which was static with no programmable objects.

The ability to interact with the DOM began with "Legacy DOM" (Level 0) in Netscape 2.0 (Sept 1995), IE 3.0 (Aug 1996), AOL 3.0 (1996, via integrated IE engine), and Opera 3.0 (1997). Then there was an intermediate phase in 1997 where Netscape 4.0 (document.layers) and IE 4.0 (document.all) each used their own model.

The first universal standard was the W3C DOM Level 1 Recommendation (Oct 1998). Major browsers adopted this slowly: IE 5.0 (Mar 1999) offered partial support, while Konqueror 2.0 (Oct 2000) and Netscape 6.0 (Nov 2000) were the first W3C-compliant engines (KHTML and Gecko).

Safari 1.0 (2003), Firefox 1.0 (2004), and Chrome 1.0 (2008) launched with native standard DOM support from version 1.0.

Currently most major browser engines follow the WHATWG DOM Living Standard to supports real-time feature implementation.

The last time I checked, Dillo also has no DOM in any reasonable definition of the term; instead it directly interprets the textual HTML when rendering, which explains why it uses an extremely small amount of RAM.

Thank you for the suggestion! Would be writing something like "DOM in the modern browsers" more correct then?

> Would be writing something like "DOM in the modern browsers" more correct then?

No, I don't think so. I don't know why the GP comment is at the top beyond historical interest. If you continue with your plans mentioned elsewhere to cover things like layout, rendering, scripting, etc, under this standard almost everything will have to have the "in modern browsers" added to it.

Part of the problem is the term "DOM" is overloaded. Fundamentally it's an API, so in that sense it only has meaning for a browser to "have a DOM" if it supports scripting that can use that API. And, in fact, all browsers that ever shipped with scripting have had some form of a DOM API (going back to the retroactively named DOM Level 0). That makes sense, because what's the point of scripting if it can't interact with page contents in some way?

So, "Lynx remains a non-DOM browser by design" is true, but only in the sense that it's not scripted at all, so of course it doesn't have DOM APIs, the same way it remains a non-canvas browser and a non-webworker browser. There's no javascript to use those things (it's a non-cssanimation browser too).

There's a looser sense of the "DOM", though, that refers to how HTML parsers turn an HTML text document into the tree structure that will then be interpreted for layout, rendering, etc.

The HTML spec[1] uses this language ("User agents must use the parsing rules described in this section to generate the DOM trees from text/html resources"), but notes it's for parsing specification convenience to act as if you'll end up with a DOM tree at the end of parsing, even if you don't actually use it as a DOM tree ("Implementations that do not support scripting do not have to actually create a DOM Document object, but the DOM tree in such cases is still used as the model for the rest of the specification.")

In that broader sense, all browsers, even non-modern ones (and Lynx) "have a DOM", since they're all parsing a text resource and turning it into some data structure that will be used for layout and rendering, even if it's the very simple layouts of the first browsers, or the subset of layout that browsers like Lynx support.

[1] https://html.spec.whatwg.org/multipage/parsing.html

I wouldn't do anything to "correct" your guide - I think it is "correct" as is. This comment is great for its informational content but I'd consider it an addendum, not an erratum.

If you like it might be nice to include a section on historical and/or niche browsers that lack some of the elements this guide describes - like e.g. Dillo which is a modern browser that supports HTML4 & doesn't support Javascript. But your guide should (imho) centrally focus on the common expectation of how popular browsers work.

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