Alternate 2 tasks within a block

Dear Psytoolkit experts,

Is it possible to randomly alternate two different tasks within a block: random typeA task on even trial numbers, random typeB task on odd trial numbers?

block iat_mixed
set &combinedcounter 0
tasklist
  typeA 16 all_before_repeat
  typeB 16 all_before_repeat
end

TypeA and typeB differ only by stimulus presented (that is, refered table). Simplified tasks look like this:

task typeA #or alternatively typeB
table tableA #typeB refers to tableB
keys a l
show text @1 0 0
readkey @2 99999999
  if STATUS == WRONG
    show text "x" 0 200 red
  fi
save @1 RT STATUS

tableA
  stimA1 1
  stimA2 1
  stimA3 1
  stimA4 1
  stimA5 2
  stimA6 2
  stimA7 2
  stimA8 2

tableB
stimB1 1
stimB2 1
stimB3 1
stimB4 1
stimB5 2
stimB6 2
stimB7 2
stimB8 2

Very gratefull in advance for any advice, Skaiste