So this one is simple conceptually

$($ifelse testexp thenexps else elseexps$)$

Example:

$($ifelse

$(>($length mylist$)10)$

$($display "the list is very long"$)$

$($display "more than $10$ elements$)$

'biglist

else

$($display "the list is small"$)$

'smal$1$list$)$

There can be any number of thenexps and elseexps BUT there is always at least one of each. eqse is a special keyword that separates thenexps from elseexps. It acts like an normal if with then statements and else statements in begin blocks.

This problem can be solved with syntax$-$cases, BUT to do so requires far more trickiness than the problem deserves. Instead, use syntax$->$datum to turn the input code into a list, transform it$,$ and then use datum$->$syntax to convert it back again.