[CCC DEV] Concerning commit 6894(ish)

[Michael Pirrone-Brusse]

Hey Fred,
    My problem seems to be less whether I'm trying to make these
side-effects happen in a PROC or a FUNCTION, and more that I can't declare
the variable to be side-effected. I should have been more clear earlier, my
apologies.

    The use-case I'm trying to get working looks like:
  BYTE aByte:
  SEQ
    analogReference (INTERNAL)
    aByte := analogRead (board.pin)

    Where analogReference sets some global variable (ADC.REF), and the
FUNCTION analogRead uses that global variable as a configuration option. It
looks like a functional language here, because, again, I'm trying to make
these calls look as much like ardino.cc's C code as I can. It's gross.
    The problem I'm not sure how to get around is that
when declaring ADC.REF outside of any PROC or FUNCTION blocks, the compiler
throws an error if I write "INITIAL INT ADC.REF ... "or just "INT ADC.REF
...".  When I write "VAL INT ADC.REF ... " I get compiler errors (in both
FUNCTIONs and PROCs) telling me that I can't assign new values to ADC.REF.
It's my understanding that all of this is proper for Occam, as
VAL declares something as a constant, and global variables... aren't.
    If you'd like to take a look at the relevant code, it's on lines 44 and
100-119 here:

http://projects.cs.kent.ac.uk/projects/kroc/trac/browser/kroc/trunk/tvm/arduino/occam/include/wiring.module

    Sorry for taking so long in explaining that... I'm really worried that
I'm wrong about half of what I've said, and there's a paragraph on some
webpage I've been oblivious to which will clear all of this up in two
minutes. I apologize if I'm being a waste of time.

    Thanks, though, for taking the time to read,
        -Drew
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