[r6rs-discuss] [Formal] Add symbol=? and boolean=?

[William D Clinger]

I am posting this as an individual member of the Scheme
community.  I am not speaking for the R6RS editors, and
this message should not be confused with the editors'
eventual formal response.

Just to clarify, I agree with most of what Lauri Alanko
wrote, and would not oppose boolean=? and symbol=?.
The point of my response was to provide some background
information regarding the efficiency of the various
comparisons.  Thanks to Lauri's response, I now
understand that efficiency was mostly irrelevant to
this discussion.

The main point on which I disagree with Lauri is also
the tacit foundation of his argument: that monomorphic 
procedures such as symbol=? are inherently clearer or
more correct than polymorphic procedures such as eqv?
and eq?.

I believe there is much to be said for simplicity and
reusability, and I regard general purpose polymorphic
procedures as an important means to those ends.

I appreciate Lauri's statement of his philosophy of
language design, because it's easy for me to get
bogged down in detailed irrelevancies (such as the
relative efficiency of predicates) when I don't
understand the underlying philosophical assumptions.

Will