Re: hook? primitive

[Mikael Djurfeldt <mdj@mdj-pc.nada.kth.se>]

Greg Badros <gjb@cs.washington.edu> writes:

> Wed Sep  8 09:18:32 1999  Greg J. Badros  <gjb@cs.washington.edu>
> 
> 	* feature.h, feature.c (scm_hook_p, scm_hook_arity,
>  	scm_hook_length): Added these predicates, and use scm_hook_p in
>  	other -hook* functions for validating the object.

Thanks.

But are all of these really necessary?  I think we should be a bit
careful with adding new primitives.

scm_hook_p should be added, but is it really useful to ask about the
arity and length of a hook?  What's the use of knowing the arity of
the hook if you don't know how to call it?

Is it really useful in practice?

(I added first class hook because I wanted it to be easier to manage
 hooks (putting them in data structures, like a fluid etc) but now I
 almost regret it.  They seem to require an unreasonable amount of
 support in the implementation.)