I've discovered a peculiarity, which may be a bug but I'm not sure yet. It affects AS 802 (5.8.0), but not AS 633.

If you try to use an escaped # in a regex using qr//x, it embeds a newline in the compiled regex. As you can see, I tried various methods of escaping the # to no avail. 

#! perl -slw
use strict;

my $re_a = qr[\w+\#];
my $re_b = qr[\w+ \# ]x;
my $re_c = qr[\w+ [#] ]x;
my $re_d = qr[\w+ \Q#\E ]x;

print $re_a;
print $re_b;
print $re_c;
print $re_d;

__END__
(?-xism:\w+\#)
(?x-ism:\w+ \#
)
(?x-ism:\w+ [#]
)
(?x-ism:\w+ \#\\E\
)

[download]

I think this is a bug, as it appears to be trying to match a \n at that position, but I'm having trouble confirming this. Any ideas how to verify this is the case?

Also, does this affect non-AS builds of 5.8?

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller


In reply to qr//x and \# weirdness (AS 5.8?) by BrowserUk

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