function(
  aa => otherfunction(),
  bb => anotherone()
);

##</code><code>##

function(
  aa => otherfunction(),
  bb => scalar( anotherone() )
);

##</code><code>##

function(
  aa => otherfunction(),
  bb => anotherone() || ''
);

##</code><code>##

my $another = anotherone(); 
<code>
function(
  aa => otherfunction(),
  bb => $anotherone
);