On Thu, 5 Dec 2002, Joseph F. Ryan wrote:
> John Williams wrote:
> >On Thu, 5 Dec 2002, Joseph F. Ryan wrote:
> >>With all of the new crazy quoting shenanagains, I'm not sure that the
> >>"balenced brackets are fine" rule will still be possible; and thus end
> >>delimeters will always need to be escaped. For instance, imagine
> >>what a nightmare this would be to parse:
> >>
> >>$var = qq[blah [\q[blah [\qq[%hash{qq[[hi]]}]]]] blah];
> >>
> >>Sure, anyone who writes something like this deserves to be shot;
> >>however, if the "balanced brackets are ok" rule still stands, the
> >>above code would be legal. (And I really, really, really don't
> >>want the above code to be legal ;)
> >
> >Well, just don't do it then. With or without balanced brackets, the
> >obfuscating programmer can do the above; he just needs more or less
> >backslashes.
>
> Saying "Just don't do it" doesn't stop someone from doing it. True,
> the example was an obfuscated one, but it was to prove a point. This is
> just as obfuscated in my opinion:
>
> $var = qq[[[%hash{qq[one]}{qq[next]}],[],[%hash{qq[hi]}{qq[there]}]]];
>
> Adding backslashes to the first example helps clear up some of the
> confusion:
>
> $var = qq[blah [\q[blah [\qq[%hash{qq[[hi\]]}]\]]\]blah];
> $var = qq[blah \[\q[blah \[\qq[%hash{qq[\[hi\]]}]\]]\]blah];
Maybe that's because you wrote it in the first place; as a reader I think
it looks just as bad, if not worse.
> Really, I think that if you really feel the need to use a delimiter
> that you know that will be in the text that you are quoting, you should
> have to go through the trouble of escaping it. Its only fair :)
No, it's not fair, because I ALWAYS have to worry about escaping
something. What I really want is a quote operator which really quotes
everything. I don't want to have to worry about what accidental "\q"
substrings are going to do in my strings. q{} was the best way to do that
in perl5, because even braces within the string were ok if they behaved
themselves.
> >'\qq[]' is the real source of evil here.
> >
> >Actually the apocalypse says:
> >
> >>RFC 226: Selective Interpolation in Single Quotish Context.
> >>
> >>This proposal has much going for it, but there are also difficulties,
> >>and I've come close to rejecting it outright simply because the
> >>single-quoting policy of Perl 5 has been successful.
> >
> >Maybe if we pushed Larry a bit, he could reject it after all?
>
> Why? I love \qq[] and \q[]. I'd much rather have embedded strings
> than be able to balance used delimiters inside quotes. I don't like the
> "balance delimeters" rule at all, and don't see it as anything more
> than an ugly hack. I'd much rather have it go than embedded strings.
I am diametrically opposed to your opinions here. I hate '\qq[]' as an
ugly hack, which ruins the non-embedding, non-quoting nature of
non-interpolated strings. If you want to embed, just use interpolated
strings.
What if \q[] was allowed in interpolated strings, but not in
non-interpolated strings. Then I'm happy with that non-interpolated
strings really don't interpolate, and you might be happy because it would
only make sense to do one level of nesting. ie, you cannot embed \qq[]
inside \q[]. Or you could do $(''), which is the same number of
characters as \qq[], and doesn't require introducing
yet-another-new-rule-to-an-already-too-complicated-escaping-system.
qq[q[
not-interpolated not-interpolated not-interpolated
not-interpolated ]interpolated\q[ not-interpolated
not-interpolated not-interpolated ]interpolated\q[
not-interpolated not-interpolated not-interpolated
not-interpolated not-interpolated not-interpolated
]interpolated\q[ not-interpolated ]interpolated\q[
not-interpolated ]interpolated interpolated
];
~ John Williams
