BlockClosure>>isClean bug?

> Hi all,
>
> I was wondering if there is a bug in BlockClosure>>isClean. As I understand it (see method comment below), the code below should evaluate to false as it closes over foo, but it does not.
>
>
> Here is the comment for isClean:
> "Answer if the receiver does not close-over any variables other than globals, and does
> not ^-return (does not close over the home context).  Clean blocks are amenable to
> being created at compile-time."
>
>
> | foo|
> foo := Time now.
> [foo] isClean
>
>
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>
> Johan Fabry   -   http://pleiad.cl/~jfabry
> PLEIAD lab  -  Computer Science Department (DCC)  -  University of Chile
>
>
>