[plt-scheme] archival docs on arity

From: David Van Horn (dvanhorn at ccs.neu.edu)
Date: Wed Sep 9 18:40:42 EDT 2009

Matthias Felleisen wrote:
> On Sep 9, 2009, at 3:33 PM, Shriram Krishnamurthi wrote:
>> I argued for the inclusion of ARITY on the grounds that some other
>> Scheme (Chez?) had it -- and I needed it for the first debugging
>> support code I wrote.
> We could ask Dan or Mitch, but I have the vague memory that even Scheme 
> 84 allowed some arity inspection, and that this may have been derived 
> from the implementation language (Franz).

I would imagine that arity inspection was available in LISPs before 
1995, but I grep'd the Scheme 84 and Franz Lisp (Opus 38.92 for VAX) 
source code and wasn't able to find any relevant occurrence of "arity".

I am generally interested in the history of arity inspection, but more 
specifically in the history in the presence of case-lambda.  So far as I 
can determine, the arity interface for PLT is the first that handles 

If Chez had it, it went away.  Now, you have object inspectors from 
which you can recover source code, from which you can calculate arities, 
but the current Chez doesn't include anything like the PLT interface out 
of the box.


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