Bill Page wrote:
>
> The bug was apparently triggered in the application of a rule but the code
> itself does not call applyQuote directly.
>
> simplifyHat:=rule
> dot(P, Q)^2-dot(P,P)*dot(Q,Q) == hat(P,Q)^2
> -dot(P,Q)^2+dot(P,P)*dot(Q,Q) == -hat(P,Q)^2
> dot(Q,R)*dot(P,R)-dot(R,R)*dot(P,Q) == dot(hat(R,Q),hat(R,P))
> --
>
> Triggers the bug:
>
> >> Error detected within library code:
> Unknown operator
>
Thanks. I see, "applyQuote" is introduced by the interpreter (rule
parser):
(1) -> parse("rule dot(Q,Q) == hat(P,Q)")$InputForm
(1) (rule (dot 'Q 'Q) (applyQuote 'hat 'P 'Q) (construct 'hat))
Type: InputForm
The quote produced by "applyQuote" is intended to prevent evaluation
of "hat" during rewrites and is removed after each rewrite by "eval"
(the one from FunctionSpace). Not nice, but makes sense.
BTW: We have:
(3) -> parse("rule dot(Q) == hat(P,Q,Q,Q,Q)")$InputForm
(3) (rule (dot 'Q) (applyQuote 'hat 'P 'Q 'Q 'Q 'Q) (construct 'hat))
Type: InputForm
so interpreter blindly creates 6 argument version of "applyQuote"
and
rule dot(Q) == hat(P,Q,Q,Q,Q)
produces error, since "applyQuote" accepts at most five arguments...
--
Waldek Hebisch
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