World: r3wp

... and - I don't buy arguments like - it is a GTDPL concept. Our 
(parse) users will not care about such statements. We are not here 
to adhere to any academic theories, but to make things usefull. If 
we wanted to adhere to what the world uses in parsing area, we should 
go the regular expressions route ...

OK, enough. I will wait how it turns out. Let's just remember, that 
we can go our own way, as parse already does. No need to turn it 
into obscure other whatever-parse-old-70ties-theory-suggests things 
...

Do you get that the concept needs a name, and that obscure concepts 
also need names? The standard syntax for this concept won't work 
in REBOL, and the only other comparable parser is the one in Perl 
6, and we can't use that syntax either, or its semantics either (it's 
compiled). This *is* guru stuff - people get PHDs about parsing. 
Carl's proposal for +'s semantics is the way that this has to work 
given how REBOL parsing is implemented.

the thing I don't  *get*  maybe you can explain, is where he adds 
the increment to the '+ ... what does that mean... really I don't 
grasp it.

Now, *that* is obscure. Noone else does that, not even Perl 6. That 
is unique.

but what does it mean?

dang ... I just *got* it...

either  [ a | b ]  [ c ] [ d ]

I don't mind the possibilities, I do care of naming and how long 
does it take for me to interpret it. If we go + route, we can change 
NOT to !, add &, II, >, -->, etc. :-)

NOT is not going to be !, for the reasons I already mentioned.

you see? looking at what Max just posted, I *imediatelly* can understand, 
what does his code do.

& makes more sense than STAY, because it relates to |. Both backtrack.

still don't see why the use of blocks is evil when its the way of 
parse for everything else.

Now I don't understand once again - if you are suggesting just changing 
the name of STAY to &, then please DON't do it!

Maxim, the a's in Carl's examples aren't involved in the expression.

Pekr, no, Carl was thinking of changing AND to STAY, but decided 
against it when he figured out how to make it infix.

Maxim, "everything is already AND by default" is not true. Everything 
is "and then" by default, which is AND with moving forward. What 
we need is AND without moving forward. An infix & handles that nicely, 
and is the opposite of the infix | meaning OR.

Ladislav just cheared to how Carl is precious about naming, and he 
liked STAY and QUOTE. STAY imediatelly expresses its meaning. Changing 
to to AND makes the situation only worse ....

So you want to rename | too?

brian  yes... I am wrapping my head around this... but I have to 
re-read the STAY proposal before getting too vocal... I'ts been to 
long since I've read it.

I actually wouldn't mind it being 'OR

(bts... about the 'a yes I didn't use the same vars in sequence... 
sorry)

[+ a |  b | c] is equivalent to [a b | not a c] but without the overhead 
or side effects being executed.

So, do you have a name for that?

This is really just - EITHER A [b][c], no?

[a b | not a c]   actually it should say... [ [a b] | [not a c]] 
  sorry but the |  doesn't roll back the a it will only roll back 
the b... its bit me too many times

No, because the a is not a condition, it's a rule.

what brian means is that the rule is consumed.... its just something 
that has to be understood.

Maxim, the a is rolled back too.

COPY is not COPY too, so what? REBOL copy value - PARSE - copy variable 
to-rule

it shoudn't be called EITHER specifically for this reason.

Brian - this is not easy to name ...

not in my experience... really it says it should and it works.. . 
until something screws it up... its happened to me COUNTLESS times... 
I've always had to put my rules in blocks to make sure they don't 
get fucked up by "|"

btw - how will you explain it to the user? Maybe it is just too new, 
but unless you provided me with [a b | not a c], I was not able to 
depict [+ a | b | c]

OK, let's try an easy one. Try to explain + without usingh the word 
"addition". Symbols are sed for a reason.

but its just being picky... the real thing... is what is evil about 
blocks?

but you see its not an addition.  its "go-over-this-and-accumulate-failure-or-not"

here... we have the precise name... its over 30 chars long   ;-)

we went too far. We should accept Steeves proposal - allow EITHER 
to be embraced as using condition OR the rule. Single as that. You 
can't beat the EITHER name. Thinking here and there, I can't imagine 
how + could be named, with the used syntax ...

Alright, explain the arithmetical - without usoing the word "subtraction". 
I had switched subjects. Oh, and don't use "hyphen" either.

actually, I think there are better words than either.

Brian - not, it is you, who can't explain it in fact. You can come 
up with a sensible name for the pattern of usage, so you throw some 
obscure symbol at us :-)

you can = you can't

Symbols mean different things depending on context, and the context 
here is parsing, not arithmetic. We still need to use them.

Max already said it - here's the name :-) "go-over-this-and-accumulate-failure-or-not"

I'm thinking  about something along the lines of   subject-to

providing

I suggested to Carl kind of syntax for the equivalenc to CASE or 
SWITCH ... maybe one of those two?

I don't need to explain Carl's + semantics because Carl was quite 
explicit in his own explanation. It made sense if you know parse 
theory, and you won't use it if you don't know parse theory. Maxim's 
term was inaccurate, though he's getting better.

PARSE itself is equivalent to CASE, so no syntax needed.

BRANCH was the best term before Carl came up with +.