Re^2: Sometimes undef is initialized and sometimes not when hash values are fed to grep

[LanX]

Here two or three workarounds (can't test the latter)

    
use utf8;
use strict;
use warnings;

use Data::Dumper;

my %h = (a => 'alfa', b => 'beta'); 



print "\n\nWorkaround 1 \n";
print map { "\t>>$_<<\n" } "$h{a}", "$h{111}", "$h{b}"; 
print "after third:\n", Dumper(\%h); 



print "\n\nWorkaround 2 \n";
print map { "\t>>$h{$_}<<\n" } qw/a 222 b/; 
print "after third:\n", Dumper(\%h); 



# print "\n\nWorkaround 3 \n";
# no autovivification;
# print map { "\t>>$_<<\n" } $h{a}, $h{333}, $h{b}; 
# print "after third:\n", Dumper(\%h);

[haukex]

can't test the latter

Unfortunately, that one doesn't work:

use warnings;
use strict;
use Data::Dumper;
no autovivification;

my %h = (a => 'alfa', b => 'beta'); 

print map { ">>$_<<\n" } $h{a}, $h{333}, $h{b};
print Dumper(\%h);

__END__

Use of uninitialized value $_ in concatenation (.) or string at 111127
+86.pl line 8.
>>alfa<<
>><<
>>beta<<
$VAR1 = {
          '333' => undef,
          'a' => 'alfa',
          'b' => 'beta'
        };

[LanX]

ugh .... :/

But I seem to remember that this glitch was also mentioned in the last thread.