You actually don't need either one. 
use constant SECOND  => 0;
use constant MINUTE  => 1;
use constant HOUR    => 2;
use constant DAY     => 3;
use constant MONTH   => 4;
use constant YEAR    => 5;
use constant WEEKDAY => 6;

my @time = localtime(time);

my $string =
    $time[WEEKDAY] + 1 . '-' .
    $time[MONTH] + 1   . '-' .
    $time[DAY]         . '_' .
    $time[HOUR]        . ':' .
    $time[MINUTE]      . ':' .
    $time[SECOND]
;

[download]
Or, if you're comfortable with join(), you could replace the last line with: 
my $string =
    join('-', $time[WEEKDAY] + 1, $time[MONTH] + 1, $time[DAY])
  . '_' .
    join(':', @time[HOUR, MINUTE, SECOND])
;

[download]

But, it's probably better to work with any of the DateTime modules on CPAN. You might want to look at DateTime, which is the up-and-coming set of modules that should do for date/time manipulation/calculation that DBI did for database access.

Being right, does not endow the right to be rude; politeness costs nothing.
Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.

In reply to Re: Optimal Date conversion? (Too much information) by dragonchild
in thread Optimal Date conversion? (Too much information) by McMahon

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