Why are you doing 
    my @records =  map  { $_->[0] }
                   sort $sort_routine
                   map  { [ $_, $_->{'title'}, $_->{'cleandate'} ] } 
                   @_;

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instead of 
    my @records = sort $sort_routine @_;

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You're slowing things down and wasting memory.

Also, 

    ($opt_g =~ /^t/i) ?    #flag setting sort order
        ($sort_routine = \&sort_by_title) :
        ($sort_routine = \&sort_by_date);

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is a complicated way of doing 

    $sort_routine = ( $opt_g =~ /^t/i
        ? \&sort_by_title
        : \&sort_by_date
    );

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I've never seen a situation where it made sense to use an assignment inside of the conditional operator (?:).

So, if your date format is really YYYY.MM.DD (and not YYYY.M.D), you get 

sub sort_records {
   my $sort_routine ( $opt_g =~ /^t/i
      ? sub { $a->{title} cmp $b->{title} }
      : sub { $a->{date}  cmp $b->{date}  }
   );   
   return sort $sort_routine @_;
}

[download]

In reply to Re: Question about map function [ANSWERED] by ikegami
in thread Question about map function [ANSWERED] by automandc

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