[Unicon-group] How to replace side effects efficiently?

[Majorinc, Kazimir]

How can I replace  f(x1,...,x10)  with side effects, i.e. one that changes 
x1,...,x10 (not structures!) without significant size increase of the 
source  in Unicon? I know I can do

every x1|x2|...|x10:=f(x1,...,x10)

but it requires rather complicated f and for some (not all) cases slowdown 
is significant.
Is there a better way?

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Kazimir Majorinc, Zagreb, Croatia