Stabilize IParser API

It’s currently flagged experimental:

https://github.com/xtermjs/xterm.js/blob/bd0d267d972a1aab4777cddecf9bf8196d7aa44f/typings/xterm.d.ts#L418-L422

@jerch any concerns about calling this stable? Any more tweaks in mind?

Not sure how many users there are but here’s VS Code’s single usage which seems to work well:

https://github.com/microsoft/vscode/blob/1beea2f864c1f403ab225dbadfdc398d76faef94/src/vs/workbench/contrib/terminal/browser/terminalInstance.ts#L499-L505

My only thought is we should think about the verb (add, register, etc.) and figure out where we want to go. I think add feels a little strange without a remove, VS Code uses register for providers/handlers/factories:

[jerch]

@sdegutis Thx for the feedback. A few notes from my side:

Right now I have to do this: […code]

Yes thats currently the only way to hook up something like a state change listener. But keep in mind that DECSET can freely stack param values, thus you will miss 1049 if its not the first param, e.g. CSI ? ... ; 1049 ; ... h.

About regexp: Your regexp idea will not work for a simple reason - the parser acts on UTF32 codepoints not strings (and I am not keen to write a regexp parser for this lol). The function identifier gets translated into numbers which form a jump table key of handlers in the parser. Thats a quite low level processing of data, but the only way to keep the parser fast (in fact the key -> target jump is still quite costly).

A more general note on regexp and ANSI sequences - its almost impossible to get this right. There are simply too many ifs and elses in the parsing state that you would have to pull into the regexp itself. I think all regexp based packages trying to strip sequences from data get this wrong. To correctly grab DECSET 1049 by a regexp it would look more like:

/(([\x1b][\[])|[\x9b])[?][0-9;]*?1049((h|l)|(;[0-9;]+?)(h|l))/

(This is still slightly wrong but who cares, guess you get my point…)

So imho regexp doesnt work here for those two reasons.

[jerch]

@Tyriar To sum this up here - from my side this looks ready to get “official”. Gonna address the documentation issue separately with an article about sequences and hooks on the website.