bug#31311: 27.0; doc of `pcase'

[Drew Adams <drew.adams@oracle.com>]

> > 2. CODE is undefined (not specified).  We say only this:
> >
> >  "The CODE expression corresponding to the matching
> >   pattern determines the return value."
> 
> I guess you missed the second line of the docstring?
>     CASES is a list of elements of the form (PATTERN CODE...).

No, not at all.  That's where CODE is "bound" in the
description, but not where it is defined.  I'm looking
for a description of CODE.

The most one can say, apparently, is that CODE is an
expression.  What purpose the sequence of CODE expressions
serves - what is done with them (or with any of them) -
isn't clear.

It talks about "the CODE expression corresponding to
the matching pattern".  Which CODE expression of the
sequence "CODE..." is "_the_ CODE expression"?  What
does it mean for "the CODE expression" to _correspond_
to the matching pattern?  (That should presumably be
"the matching PATTERN, BTW.)

Sorry, but it's just not clear.