DRAFT, 3-NOV-2003

SVA 3.1A PROPOSAL:  SAMPLING LOCAL VARIABLES
--------------------------------------------

DISCUSSION:

In SVA 3.1, local variable sampling can be attached only to a boolean
expression.
        
This proposal makes coding of the sampling of local variables simpler
by allowing sampling to occur after any sequence expression, not just
booleans.  This extension is an abbreviation for a capability that
already exists in the language.

The syntax is

   ( sequence_expr , identifier = expression )


EXAMPLE:  As an alternative to

   (r1 and r2) ##0 (1'b1, v = e)

one can code

   (r1 and r2, v = e)

////


SEMANTICS
---------

"(sequence_expr, v = e)" is a derived form, semantically equivalent to
"sequence_expr ##0 (1'b1, v = e)".


MULTIPLE CLOCK SUPPORT
----------------------

This proposal does not change the multiple clock support for local 
variables.

Sampling of local variables occurs within a singly-clocked sequence,
although the local variables can flow out of that sequence.


