Re: a note on notations

[Alan Watson <alan@oldp.astro.wisc.edu>]

> <>foo works just fine in es-.08; it's used all
> over the place in initial.es, normally as <>$&primitives.

Oops.  I'm suffering from the ol' rc/es schizophrenia again.

> > This cannot be the case for either $ or %
> > as $foo and %foo already have essential meanings.
> 
> no, but
>	 ; echo % true
>	 0
>	 ; echo %(false)
>	 1
>	 ; 

Maybe I'm just really dumb, but this particular overloading looks like
it could get very confusing indeed.  And notice that

	; echo `ls

works, but

	; echo %ls

doesn't. 

However, since you and Byron both think that `foo is a good idea, my
chances of getting you to drop it and only allow `{foo} and <>{foo} (or
%{foo} or ${foo} or whatever) are about as small as my chances of
getting John to compile es with readline using gcc (but perhaps the
effort is not quite so misguided).

Think about what `foo actually gives you over `{foo}, and think about
the benefit of the visual simplification of insisting on enclosing {}
for both ` and <>.  You GAIN two distict constructs (namely, `foo and
<>foo) for further expansion -- if we're running out of characters at
v0.8, how much more will we need them in v1.8?  There are many
constructs I avoid in rc and es because more visually distinctive but
otherwise equivalent constructs exist -- readability is damned
important -- and `foo falls into this category.

> $& has everything to do with lookup:  it looks up a procedure pointer
> in a dictionary of primitives.  see prim.c.

Just because you chose to implement it as a lookup doesn't mean it
intrinsically has ANYTHING to do with lookup in the sense that $foo
does.  The $& primitives are primitives -- end of story.  Is there
anything in their semantics which forces them to be implemented in 
the same manner as a generic $foo?  Am I just being dumb?

%%foo is at least clearly related to %foo; $&foo is not.

Finally, if you take away my ability to use % as a command name, I'm
going to be spitting PASTEL PINK comets with BRIGHT ORANGE spots and
LIME GREEN stripes.  Take a look at my email address if you doubt
it...