[Series-users] Some basic usage questions.

[Robin L. P. <rlp...@di...>]

Brand new to Series, but it seems like my sort of thing; I always
kind of enjoyed the lazy evaluation stuff that Haskell did.

For this particural bit of code, I'm starting with finite lists and
digging through them to find sub-sections.  I'm a little surprised
by some of the warnings I'm getting, and I'm hoping someone can shed
some light on these.  Everything seems to be working just fine, for
the record.

Restriction violation 12 in series expression:
NIL
Series var INITIAL-SER referenced in nested non-series LAMBDA.
WARNING:
Warning 28 in series expression:
(COLLECT-FIRST X)
Non-series to series data flow from:
X
to:
(COLLECT-FIRST X)

The goal of the function in question is to turn a (finite) series
into a series of all the possible sub-series; there are *no*
non-series calls in the function:

(defun subseries-all (start-ser)
  (DECLARE (OPTIMIZABLE-SERIES-FUNCTION))
  (multiple-value-bind
    (index-ser initial-ser)
    (cotruncate (scan-range) start-ser)
    (mapping ((x index-ser))
             (subseries initial-ser x))))

Just to be clear, initial-ser and start-ser should be the same in
all respects; I couldn't figure out any other way to get a 0-to-n
series of the same length as start-ser.  There's no way I can see to
get the legth of a finite series.


WARNING:
Warning 28 in series expression:
(DEFUN SPATH-FIND (SER ITEM) (DECLARE (OPTIMIZABLE-SERIES-FUNCTION))
       (CHOOSE-IF
        #'(LAMBDA (X) (FORMAT T "val: ~A~%" X) (EQUAL ITEM (COLLECT-FIRST X)))
        (SUBSERIES-ALL SER)))
Non-series to series data flow from:
(SUBSERIES-ALL SER)
to:
(CHOOSE-IF
 #'(LAMBDA (X) (FORMAT T "val: ~A~%" X) (EQUAL ITEM (COLLECT-FIRST X)))
 (SUBSERIES-ALL SER))
WARNING:
Restriction violation 13 in series expression:
(COLLECT-FIRST (SPATH-FIND (SCAN '(B 3 C 1 B 5)) 'B))
Series to non-series data flow from:
(SCAN '(B 3 C 1 B 5))
to:
(SPATH-FIND (SCAN '(B 3 C 1 B 5)) 'B)

Both of these come from the same function, spath-find, helpfully
printed there in its entirety.

The point of the choose-if predicate (ignoring the format call) is
to compare the first item of the series (remember, subseries-all
returns a series of series) to a given value. I'm quite surprised by
the total lack of accessors; there's no way that I can see to get at
the first element of the sub-series there at all without converting
out of series mode and getting those warnings.  I'm hoping someone
can show me something I missed.

Thanks.

-Robin

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