Didn't you mean this, rather? 
sub nearest{
    my ( $dist, $href ) = @_;
    my ( $answer ) = ( sort { abs( $a - $dist ) <=> abs( $b - $dist ) 
+} keys %$href )[0];
    return $href -> { $answer };
}

[download]
Otherwise this is a great trick, thanks!

In reply to Re^2: Lookup closest hash key by Anonymous Monk
in thread Lookup closest hash key by Just in

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