#!/usr/bin/perl -w
use strict;

my $data = {
    Colour  => 'blue',
    Entries => {
        Flowers => {
            Dahlia => {
                Smell => 'nice'
            },
            Rose   => {
                Colour => 'red'
            }
        }
    }
};

my $ref_flowers = $data->{Entries}->{Flowers};

my $colour = sub {
   my $flw=shift;
   $ref_flowers->{$flw}->{Colour} || $data->{Colour}
};

print "Rose's color is ",$colour->('Rose'),"\n";
print "Dahlia's color is  ", $colour->('Dahlia'),"\n";

__output__
Rose's color is Red.
Dahlia's color is Blue.
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