Add basic `DOCTYPE` support

[kristian]

Hey @matteodelabre, I am considering using your library for my XML minifier minify-xml, however parsing documents with a DOCTYPE resulting in a error is a blocker for me at this point in time. How about and how would you judge the effort adding basic DOCTYPE support, similar to processing instructions soon? Content parsing, similar to parseAttrs could be added later on and for my (many other purpose) getting an event with a content field would be enough for me and is in fact much better than just throwing an error for an otherwise valid document.

What do you think? Any chance of you adding this, or could you explain what was the complication to not having it added in the first place? Thanks!

[matteodelabre]

Hi kristian, from what I can tell, adding support for doctypes should not be that hard. I left it out initially since I didn’t need it, but of course I would be open to adding it. I can’t promise I’ll work on this soon unfortunately, as I have some pretty busy weeks coming.

[kristian]

@matteodelabre sure, no worries! Let me see what I can do. If I provide you with a PR, you my find a minute to review it! :) As long as there is nothing that generally complicates it, adding DOCTYPE support shouldn't be that hard I hope. Let me see what I can do! 👍

[codalf]

@matteodelabre: Is there a way, that I can support this issue? We'd also need DOCTYPE support...