Re: Question on pcase

[Alan Mackenzie <acm@muc.de>]

Hello, Stephen.

On Sat, Oct 24, 2015 at 02:58:54PM +0200, Stephen Berman wrote:
> On Sat, 24 Oct 2015 09:01:46 +0000 Alan Mackenzie <acm@muc.de> wrote:

> > 2. "Semantics", as a noun, is always plural in English (a bit like
> > "Eltern" in German).

> It's morphologically plural but syntactically singular, like "physics"
> -- at least in American English, but I think also in British English; or
> would you really say "Semantics are the study of meaning" or "Semantics
> are a science, and physics are, too"?  Hence, I think in

Yes, my mistake.

> > -;; All yet to understand is the semantic each of the basic PATTERNs.
> > +;; All that remains to understand are the semantics of each of the basic PATTERNs.
>                                      ^^^
> "are" should be replaced by "is".  (Even if "are" is acceptable here in
> British English, AFAIK the standard for GNU documentation is American
> English.)

Indeed, that "are" should be an "is".

> > -;; fulfils eihter `arrayp' or `numberp'.  And 3 if the binding of x is
> > +;; fulfils either `arrayp' or `numberp'.  And 3 if the binding of x is
>       ^^^^^^^
> I believe "fulfills" is the usual spelling in American English.

I just looked that one up.  "fulfills" is indeed the usual American
English spelling, "fulfils" being the British English spelling.

> >  ;; This is a pattern form that allows you to match a pattern PAT
> >  ;; against an _arbitrary_ expression EXP.  This is not special,
> > -;; matching PAT is done as you have learned, just against the EXP you
> > +;; matching PAT is done as you have learned, just on the EXP you
> >  ;; specify there, and not the EXPRESSION given to pcase at top level.

> Why replace "against" with "on" here but not in the preceding line?  I
> think "against" is usual in this context.  A somewhat better formulation
> is this, IMO: "The only difference from the pattern matching you have
> learned is that PAT is matched against the EXP you specify here..."

Oh, no!  This is complicated, too.  Perhaps the best preposition for
"match" here is "with", on the grounds that harmony is expected rather
than a fight.  You might match one sporting team against another, but
you'd match the colour of an item of clothing with that of another.  Or
something like that.

> > -;; If you are used to understand grammers: the above description of
> > -;; `QPAT describes a quite simpel grammer.  You make like to try it
> > +;; If you are used to understanding grammars: the above description of
> > +;; `QPAT describes a quite simple grammar.  You might like to try it

> I think a somewhat better formulation is this: "If you are familiar with
> formal language grammars, the above description..."

Possibly.  But that's rewriting the original, rather than correcting it.

> Steve Berman

-- 
Alan Mackenzie (Nuremberg, Germany).