Not always true. It is posible to prevent a loop from holding up processing of events. Using signals and timers. Really intense loops could be implemented in this way...
Code:
; *** Multi-Threaded Looping, using Timers ***

; Starts everything going
alias test {
  set %LoopCount 1
  .signal do_echo | .signal do_loop
}

; do_loop will not stop looping,
; nor will this type of looping stop event processing
on *:signal:do_loop {
  inc %LoopCount | .timerSig1 1 0 .signal $signal
  halt | :error
  echo -a Break in $signal at LoopCount of %LoopCount $+ . $error
  .timerSig1 off | .timerSig2 off | reseterror
}

; do_echo will stop when loop count is >= 1000
; and also stop script processing, stoping the first loop
; Like the prior loop does not stop event proesssing
on *:signal:do_echo {
  if (%LoopCount < 999) {
    echo -a Loop Count: %LoopCount
    .timerSig2 1 0 .signal $signal
  }
  else { remote off | .timerSig1 off | .timerSig2 off }
  halt | :error
  echo -a Break in $signal at LoopCount of %LoopCount $+ . $error
  .timerSig1 off | .timerSig2 off | reseterror
}

NaquadaBomb
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