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Mobile Variables

Mobile variables: errata

My test for ownership was wrong.

  x = x
    c ! VAR x

should STOP rather than return FALSE if x is not owned. So
maybe we really do need a new key word to make the test?
"OWN x" perhaps as I originally suggested?

And, unless someone can suggest another way to test for ownership,
we might want OWN as well. Please apply the razor and get rid of OWN.
I suppose that we might require that programs be written in such a way
that these tests are not required. One could always claim the variables
some central process, and collect access rights via VAR channels. Then
ALTing gives a way of waiting for the variables. I think that is too
restrictive, and might lead to inefficient and obstruse code.

Of course, one way is to overload CLAIM with yet another meaning:
could return a boolean. I think that is ugly.


A E Lawrence, MA., DPhil.  	adrian.lawrence@xxxxxxxxxxxxxx
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