perl

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# always use strict and warnings, this can solve hours of debuging!
use strict;
use warnings;

use Cache::FileCache;

# defined somewere else...
my $dbh;
my $t;

my $cache = new Cache::FileCache( );
# $cache->clear(); # clear all cached information.`

# this subroutine works just fine
sub stockInfoFresh
{
	my ($tick) = @_; # this is a better way to get arguments
	
	$tick =~ tr/a-z/A-Z/; # to uppercase
	
	my $first_let = substr($tick,0,1);
	
	my $name = "Ticker not found";
	my $exch = '';
	
    my $sth = $dbh->prepare("SELECT * FROM `Stock` WHERE `Ticker` = '$tick'"); $sth->execute;
	
    # this implies that you will work with one and only one row.
    # if multiple rows this should be inside a while loop.
    my @stockid = $sth->fetchrow_array;
	
	if ($stockid[0]) {
		$name = $stockid[1];
		$exch = $stockid[2];
	}

    $sth->finish;
	
    # when returning a array try to avoid return a array as
    # ($one, $two, @three), this syntax can raise difficult bugs.
	return($tick, $first_let, $name, $exch, $stockid[0]);
}

# this subroutine fails
sub stockInfo
{
	my ($tick) = @_; # this is a better way to get a argument

    # get returns a array reference, you should get in a scalar
    # just to test if FileCache returned something    
	my $stockInfo = $cache->get( "stockInfo" . $tick );

    # I will save the result in this array.
    my @stockInfo;

	if( not $stockInfo  )
	{
		@stockInfo = &stockInfoFresh($tick);
		
		$cache->set( "stockInfo" . $tick, \@stockInfo, "1 hour" );
	}
    else {
        # if FileCache returned something is a reference to an array
        # so now lets dereference it.
        @stockInfo = @{$stockInfo};
    }

	# at this point, $stockInfo[0] is empty

	return @stockInfo;
}


my($tick, $first_let, $name, $exch, $stockid) = &stockInfo($t);


print "$tick $first_let $name $exch $stockid\n";