Fir a start that probably doesn't do what you mean. Consider:

use warnings;
use strict;

my $drink;
my $punter = 'coffee';

if($punter eq 'coffee'){ $drink = 'non alky'; }
if($punter eq 'beer'){ $drink = 'alky'; }
if($punter eq 'whisky'){ $drink = 'proper alky'; }
else { $drink = 'unknown'; }

print $drink;
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Prints:

unknown
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Better would be:

use warnings;
use strict;

my $drink;
my $punter = 'coffee';

if ('coffee' eq $punter){
    $drink = 'non alky';
} elsif ('beer' eq $punter){
    $drink = 'alky';
} elsif ('whisky' eq $punter) {
    $drink = 'proper alky';
} else {
    $drink = 'unknown';
}

print $drink;
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which prints:

non alky
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as expected. However probably better still would be:

use warnings;
use strict;

my %drinkType = ('coffee' => 'non alky', 'beer' => 'alky', 'whisky' =>
+ 'proper alky');
my $drink;
my $punter = 'coffee';

if (exists $drinkType{$punter}) {
    $drink = $drinkType{$punter};
} else {
    $drink = 'unknown';
}

print $drink;
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If you have more work to do for each if clause you could:

use warnings;
use strict;

my %drinkType = ('coffee' => \&doNonalky, 'beer' => \&doAlky, 'whisky'
+ => \&doProperAlky);
my $drink;
my $punter = 'coffee';

if (exists $drinkType{$punter}) {
    $drinkType{$punter}->();
} else {
    print 'unknown';
}


sub doNonalky {
    print 'non alky';
}

sub doAlky {
    print 'alky';
}

sub doProperAlky {
    print 'proper alky';
}
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