Parsing nested markup objects

[Laith Bahodi]

Hi! I'm working on a parser for org and I noticed something about
nested markup in the syntax spec: markup starting at the limit of
another object seems like it shouldn't be interpreted as markup. The
spec says that the precondition characters are:

PRE MARKER ...
PRE
  Either a whitespace character, -, (, {, ', ", or the beginning of a line.
https://orgmode.org/worg/dev/org-syntax-edited.html#Emphasis_Markers

With links, since `[` isn't in that list, the spec seems to imply the
following wouldn't contain an italic block, but it does:

[[https://example.com][/according to the spec, this shouldn't be marked up/]]

same goes for  */abc/* (since `*` isn't in the set defined by PRE)

I understand why it works like this since it's pretty convenient, but
I feel like the details about this interaction should probably be
clarified since it's not quite obvious from the spec (unless I missed
something!).

Also, how are these objects intended to be handled? I couldn't
pinpoint where in `org-element` this is approached.