Convert dotless to a submodule

[T0mstone]

This makes more conceptual sense to me, since dotless on its own is meaningless.

This is a breaking change, so three approvals are necessary.

Note that there is no way to do a deprecation for this, but I don't think anyone was using dotless without modifiers anyway.

[Enivex]

I really don't see the issue with having no top level symbol.

Naming will always be a result of compromises.

If someone truly wishes to write dotless instead of dotless.i, then let them.

[MDLC01]

I think the change I would like instead is to change dotless.i and dotless.j to i.dotless and j.dotless instead. Especially because some symbols that we may want to add in the future are also variation of Latin letters that would benefit from this naming schema (e.g., F.inv for U+2132 Ⅎ, G.inv for U+2141 ⅁, L.inv for U+2142 ⅂, L.rev for U+2143 ⅃).

Of course as of now those would not be accessible in Typst math, but I think it may be sensible to allow the base identifier of a field access to be a single letter in math (the same way the identifier after the period can already be a single letter). @isuffix thoughts?

[Enivex]

I think single letter identifiers would be a bad idea.

Something like

and therefore
$
 a = b + c.
$

would now presumably be a syntax error.

Your examples could (almost) equally well be inv.F, inv.G, inv.L, rev.L, with the added benefit that all such characters would be grouped.

[T0mstone]

Something like

and therefore
$
 a = b + c.
$

would now presumably be a syntax error.

Well, $ alpha + beta = gamma. $ is not a syntax error today, so I wouldn't think so.

[Enivex]

Fair enough, but I still strongly dislike the idea.

[T0mstone]

Well, I strongly dislike having things that work like modifiers before the base symbol name. It's the opposite of consistent.

[Enivex]

Well, I strongly dislike having things that work like modifiers before the base symbol name. It's the opposite of consistent.

It's impossible to achieve complete consistency. That's why I mentioned compromises above.

And even if you could achieve perfect consistency, that may not necessarily be the most usable option.

[knuesel]

I also think single-letter identifiers are probably a bad idea and that i in math should be either a letter or a symbol binding, but not "both, it depends...".

@Enivex I can see that the current state can seem no big deal but is there a downside to the proposed change (other than breaking the code of someone that writes dotless instead of dotless.i)? It does seem conceptually more correct...

[MDLC01]

I also think single-letter identifiers are probably a bad idea and that i in math should be either a letter or a symbol binding, but not "both, it depends...".

A single letter can already be interpreted as an identifier, such as i in dotless.i. So it already depends on the context.