"abc" =~ /a/;
it suddenly starts outputting "Outside if", because /$var/ runs the last successfully matched regex if there was any (see The empty pattern //). If you don't want this behaviour (and I bet you don't), never use a match with fully dynamic contents. You can change it to /(?:$var)/, so that the pattern doesn't get empty after interpolating the variable.
Update: There probably should be a perlcritic policy forbidding a potentially empty regex match.
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
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if ($line =~ /$var1|$var2/i && $check =~ /YES/i) { print "Inside if\n"
+;}
else {print "Outside if\n";}
Of course if we still have $var1 = '' then it will still match but that's a question for KishKishore as to what they actually intend.
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[d/l]
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Good point!
So, e.g. by reversing the order of substatements inside the IF statement gives opposite result.
if(($check =~ m/YES/i) and (($line =~ m/$var1/i) || ($line =~ m/$var2/
+i))) { print "Inside if\n";}
else {print "Outside if\n";}
...unless ($check =~ m/Y/i) :) | [reply]
[d/l]
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Thanks choroba,
I didn’t know that! This special case must have been implemented for a reason, but I can’t think what it could have been.
Using a non-capturing group to avoid this behaviour is a useful workaround.
The good news is that this special case doesn’t seem to be present in Raku:
23:48 >perl -wE "my $s = ''; say 'match1' if 'abc' =~ /b/; say 'match2
+' if 'adc =~ /(?:$s)/;"
match1
match2
23:55 >perl -wE "my $s = ''; say 'match1' if 'abc' =~ /b/; say 'match2
+' if 'adc =~ /$s/;"
match1
23:56 >raku -e "my Str $s = ''; say 'match1' if 'abc' ~~ /b/; say 'mat
+ch2' if 'adc' ~~ /$s/;"
match1
match2
23:56 >
Cheers,
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