Dear Monks,

I'm stuck on "delayed-regex assertions" here.

Can "delayed-regex assertions" be nested with perl v5.8.6 built for MSWin32-x86-multi-thread on win xp SP2 32bit?

When I tried this I get:
Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/(??{ <-- HERE join( '|', grep ( /

I gave anonymous sub routines a shot but didn't get far there.

Code example:

<code> use Data::Dumper;
my @A = ( "ab", "abcd", "f" );
my %H = (
'ab' => 0,
'abcd' => 1,
#'def' => 2,
);

# 1st working alternative
foreach $i (@A){if (!(grep (/$i/i, keys %H))){print "$i\n";};};


# 2nd working alternative
@B = grep ( /(??{join( '|', @A)})/gi, keys %H );
@B = grep ( !/(??{join( '|', @B)})/gi, @A );

# Imagined Code with the issue
# @B = grep ( !/(??{join( '|', grep ( /(??{join( '|', @A)})/gi, keys %H ) })/gi, @A );

# Issue Code Perl -c output
# Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/(??{ <-- HERE join( '|', grep ( /
print "Delta:\n";
print Dumper(@B);


##Output
##Delta:
##$VAR1 = 'f';
< /code>


Many, many thanks in advance.

ddn123456

In reply to Can "delayed-regex assertions" be nested... by ddn123456

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