> Date: Tue, 9 Sep 2003 16:19:45 -0400
> From: Ray Denenberg <[log in to unmask]>
>
> > No, just because the grammar specifies that the "and" binds tighter
> > than the prefix mapping. It's exactly analogous to the way that
> > arithmetic in nearly all programming languages knows that a+b*c means
> > a+(b*c) rather than (a+b)*c -- because "*" binds tighter than "+".
>
> But we don't have operator precedence in cql, it's left-to-right.
Ah contraire. We _do_ have operator precedence. For example, all the
relations bind tighter than all the booleans so that
dc.title=dinosaur and farlow
means
(dc.title=dinosaur) and farlow
rather than
dc.title=(dinosaur and farlow)
It is true that all _binary_ operators have the same precendence --
just as "+" and "-" have the same precedence in most programming
languages. But that's only part of the story.
> (And even if we did, who says "and" takes precedence over a prefix
> assignment. I don't mean to be ornery here, but I don't think this
> is nailed down.)
Who says? The BNF does! That's what it's for!
_/|_ _______________________________________________________________
/o ) \/ Mike Taylor <[log in to unmask]> http://www.miketaylor.org.uk
)_v__/\ "You cannot really appreciate Dilbert unless you've read it
in the original Klingon." -- Klingon Programming Mantra
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