The literals vocabulary contains words to run code at parse time and insert the results into more complex literal values.
USING: kernel literals math prettyprint ;
IN: scratchpad
<< CONSTANT: five 5 >>
{ $ five $[ five dup 1 + dup 2 + ] } .
{ 5 5 6 8 }
{ 5 5 6 8 }
$
$[
${