[armedbear-devel] translate-logical-pathname and :wild-inferiorsregression

[Mark Evenson]

On 1/29/10 4:12 PM, Alan Ruttenberg wrote:
> On Fri, Jan 29, 2010 at 4:03 AM, Mark Evenson<evenson at panix.com>  wrote:
>> On 1/18/10 4:51 PM, Alan Ruttenberg wrote:
>>> (TRANSLATE-PATHNAME #P"IDO:IMMUNOLOGY;" #P"IDO:IMMUNOLOGY;**;*.*"
>>> #P"/Users/alanr/repos/infectious-disease-ontology/trunk/src/ontology/**/*.*")
>>
>> Acknowledge and logged as [ticket 82][1].
[…]

Somehow, the more I learn about Pathnames, the less I understand.

First off, I think that the SETF on LOGICAL-PATHNAME-TRANSLATION should 
never use the #P for its arguments as you had in your example:

(setf (logical-pathname-translations "ido")
    '((#P"IDO:IDO-CORE;**;*.*" 
#P"/Users/alanr/repos/infectious-disease-ontology/trunk/src/ontology/ido-core/**/*.*")))

[…]

because it doesn't do what you might expect, namely the 
#p"IDO:IDO-CORE;**;*.*" is not interpreted as a logical pathname when 
read by the SHARP_P reader.  You end up with an Pathname whose NAME is 
"IDO:IDO-CORE;**;*.*" and other components are nil.  That this ever 
worked in ABCL is mysterious.  Based on a canvas of open source Lisps 
available to me, SBCL, ECL, and CCL all signal errors on being input 
this form, for a variety of differing reasons.  clisp accepts the form, 
but fails to record it as a logical pathname.

Second, refactoring your test case away from logical pathnames down to 
the use to TRANSLATE-PATHNAME, I derive the following use of 
TRANSLATE-PATHNAME to be equivalent to the behavior you want:

   (translate-pathname "/immunology/" "/immunology/**/" "/usr/home/**")

which you want to output

   #p"/usr/home/immunology/"

but none of the other Lisps I checked (SBCL, ECL, CCL, and clisp) work 
this way, they all return

   #p"/usr/home/"

I think they do this to avoid the case for which Thomas Russ reported a 
bug where

   (translate-pathname "/immunology/" "/immunology/**/" 
"/usr/home/immunology/**")

should return

   #p"/usr/home/immunology/"

not

   #p"/usr/home/immunology/immunology/"

as was the pre-r12283 ABCL behavior.

So, I am a bit confused on how to proceed.  The behavior of 
TRANSLATE-PATHNAME is implementation specific.  From fuddling around 
with the old implementation and the new one, I seem to be able to get 
either behavior but not both and they seem logically incompatible but I 
haven't proved that definitely to myself.  Since the other CL 
implementations exhibit the same behavior as current ABCL I need either 
a) evidence that another Lisp works the way that Alan expects (and does 
it then exhibit the same behavior that is a bug to Thomas Russ?) or b) a 
clear semantics that I can implement that satisfy both uses.

Input kindly solicited from one and all.

-- 
"A screaming comes across the sky.  It has happened before, but there
is nothing to compare to it now."