Re: Code for cond*

[Richard Stallman]

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  > Your syntax (FUN VAR ARGS...) has two disadvantages in my view:

  > - It fixes the argument to be checked as the first argument.
  > - It does not syntactically distinguish the VAR from the normal
  >   arguments, making a bit too magical for my taste.

I think this is not a real disadvantage.  The more general kind of
constrained variable, with `constrain', does not have those two
limitations.

The simple version variable, (PRED VAR OTHER-ARGS...), is an
abbreviation which handles the usual cases in a very convenient way.
For the cases it does not handle, just use `constrain'.

The special nature of the first argument is something that users
will get used to as they see many instances of cond*.

  > Of course, there remains the question whether this usage should be the
  > one that gets the privilege of not needing a dedicated "keyword", i.e. to
  > allowing using it without the surrounding `pred`:

  >     (FUN ,VAR ARGS...)

If this syntax is easy to implement and doesn't cause difficulties, I'll
go along with it if people prefer it.



-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)