\setlength{\unitlength}{0.01cm}
\nop{
)
}
\hspace{1.0cm}
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\nop{
\small
We assume that O is bound to , the constructor process
for the object $(c,n)%b' = (c,n,k)%bobj(%b) = obj(%b')%b'O!m(t)%b%aQ?m(t)%b'%bm(t)%a%b'%aQ?%b
for the object ,
may then proceed with the evaluation of the constructor goal.
When backtracking occurs in , the goal succeeds as many
times as there are alternative answer substitutions produced
by .
Backtracking in runs concurrently with the activity
of process .
}