Using the ternary operator: 
my $rain = 1;
my %Weather = (
    'precipitation' => ($rain == 0) ? 'dry' : 'wet',
);

[download]
Or even: 
my $rain = 1;
my %Weather = (
    'precipitation' => $rain ? 'wet' : 'dry',
);

[download]
The way to use the if/elsif construct: 
my $precipitation;
if ($rain == 0) {
    $precipitation = 'dry';
}
elsif ($rain == 1) {
    $precipitation = 'wet';
}

[download]
See perldoc for Conditional Operator and Compound Statements, and also strict and warnings

In reply to Re: Conditional within Hash definition by tangent
in thread Conditional within Hash definition by veryan

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