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Re: [engelang] Re: Self-segmenting words & the treatment of names

Mart�n Bald�n, On 16/05/2006 00:07:
--- In engelang@yahoogroups.com, And Rosta <a.rosta@...> wrote: 


As I said in one of my messages yesterday, fixed arity means no

brackets, and variable arity needs just an unlabelled right bracket.
And in reverse polish, you need just an unlabelled left bracket.

But variable-arity, nested expressions need nested parenthesis, and
their numbers can grow quickly. Having lots of brackets in a row is
both verbous and confusing, that's the reason for using labeled
brackets.
Have two right brackets. One marks the final operand and precedes it. This avoids nesting. The other marks either zero arity and follows the operator, or else precedes the first operand. 
And I don't think having right brackets only is enough for
my purposes. Let's see:
How would you represent the following expressions?: 

exp1: (and (or a b) (xor c d ) e )

exp2: (and (or a b (xor c d) ) e )

Would it be something like this? :
exp1: and or a b) xor c d ) e exp2: and or a b xor c d) e 
I suspect it is. This seems much more concise, but there's a catch:
you are assuming that some
lexemes, such as "and", "or" and "xor" have the privileged status of
operators, 

Yes.
while others, like "a", "b", "c", "d", "e" don't, and so they can never be the "head" of an expression, only its arguments. 

No.


In Lisp, you can define new operators
all the time, and the syntax is unafected, which gives Lisp its
legendary flexibility. The problem is that you also need more
brackets. The key is to make use of this flexibility in clever ways,
to keep a reasonable number of brackets. A frequent trick is using
macros, with which you can get results just as concise as in other
notations, with the advantage that it's fully customizable. Actually,
some Lisp fans say that the ease of making powerful macros is one of
the key strong points of Lisp. So, I'll have to study the issue of
Lisp macros and see how to implement them in a spoken language.
Meanwhile, I thought it was a good idea to have a user-friendly
notation for deeply nested brackets, since I know I'll need them.


Can you give some sort of example -- a hypthetical example in your conlang, I mean? I don't grasp what the catch is yet.

--And.