Two points to critique. First, as is pointed out, $flag isn't a global variable once you discount the fact that you're using global code. Second, don't re-invent wheels. Download and install IO::Prompt, and then you can do something like this: 

#!/usr/bin/perl
use strict;
use warnings;

use IO::Prompt;

sub main
{

    my @positions = qw(sitting standing reclining);
    my @locations =
        ('at the museum', 'in the woods', 'on the beach', 'in the kitc
+hen');
    my @drinks = qw(scotch beer coke yoohoo);
    my $flag   = 1;

    do {
        my $selection = prompt
            -p => 'The bartender asks what you want:',
            -onechar => 1,
            -menu => \@drinks;

        $flag = do_it( $selection, \@positions, \@locations );

    } until $flag == 0;
}

sub do_it {
    
    my $drink         = shift;
    my $positions_ref = shift;
    my $locations_ref = shift;
    my $rand_position = $positions_ref->[ rand( @$positions_ref ) ];
    my $rand_location = $locations_ref->[ rand( @$locations_ref ) ];
    
    print
        "You just drank a $drink $rand_location in the $rand_position 
+position.\n";
    
    if ( $rand_location eq 'on the beach' ) {
        print "YEEEEEHAAAWWWWWWWWWW!\n";
        return 0;
    }
    else {
        return 1;
    }
    
}

main;

[download]
Note how I took your global code, pushed it into a sub, and then called it. Now your $flag isn't global. And now you have to pass the positions and locations refs into do_it, whereas before, it wasn't strictly required (due to the global nature of the variables).

I've already taken into account Anomolous Monk's observance on the usage of rand.

In reply to Re: Repeating an input prompt by Tanktalus
in thread Repeating an input prompt by zod

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