From Andrew Patterson:
With respect to ADL quoting rules...
...what should the behaviour be when a
\ is used without a valid 'quotation' character following i.e.
and \" should be interpreted as \ and " respectively, but should
\. be interpreted a one character . or two characters \.? I'd suggest
that if the quotation character is not recongised, then it should
be an error.
Furthermore, what are the rules around the &#xHHHH escape
sequence? Surely the & will have to be quoted as well? Otherwise
how will the parser know when it is being used for a mnenomic?
Wouldn't a unicode escape technique such as used in Java and C#
(\uAABB) be a better approach (i.e. one that fits in more
comfortably with the standard \" quoting rules).
Finally, what about the other standard string escapes used
in Java and C# (\t, \b etc). Is there any room for them (maybe
in ADL 2.0?)
The basic problem here is to have a consistent way of doing the following:
quoting literals like the " and ' characters (currently uses a backslash)
allowing other quoted characters such as \r, \n, \t etc - what is the list?
quoting unicode characters. Is this needed given that real unicode can be used?
It may be needed for systems and transmission in situations where unicode (or
any non-ascii) cannot be tolerated. But we probably want a way of differentiating
between proper unicode files and ASCII fles containing quoted characters.