[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: [mizar] widening BinOp to Relation



On Fri, 2 Feb 2007, Jesse Alama wrote:

Adam Naumowicz <adamn@math.uwb.edu.pl> writes:

On Fri, 2 Feb 2007, Jesse Alama wrote:

It seems that you don't have RELSET_1 present among your registrations
directives. Tracing back the widening relation of BinOp of A one comes
to Subset of [:A,A:] which is Relation-like only in the presence of a
suitable registration from RELSET_1 - the first one.

Please let me know if this solved the problem.

You were right -- including RELSET_1 in the registrations directive
solved the problem.  How did you know to look at RELSET_1?

Expanding the mode 'BinOp of A' we get 'Function of [:A,A:],A', which
in turn expands to 'quasi_total PartFunc of [:A,A:],A', and this means
'Function-like Relation of [:A,A:],A' which is eventually redefined as
Subset of [:[:A,A:],A:]' in RELSET_1. The registration that follows
this redefinition completes the job - providing the 'Relation-like'
attribute:

registration let X,Y;
 cluster -> Relation-like Subset of [:X,Y:];
end;

I follow the reason why my problem is solved given your hint to look
into RELSET_1.  But how did you know that RELSET_1 contained the key
to the solution?  Does this come from your knowledge of the MML?  An
MML query?  A mizar-mode command?

I must admit that my knowledge of MML alone wouldn't suffice to figure this out - I used the "View symbol def" feature for browsing in abstracts in Emacs - some knowledge of MML helped to speed up the search for the right occurrence of the symbols in question, though.

Best,
Adam Naumowicz

======================================================================
Department of Applied Logic            fax. +48 (85) 745-7662
Institute of Computer Science          tel. +48 (85) 745-7559 (office)
University of Bialystok                e-mail: adamn@mizar.org
Sosnowa 64, 15-887 Bialystok, Poland   http://math.uwb.edu.pl/~adamn/
======================================================================