Re: The Logical Pathname (Song)

This is CCL

CL-USER> *(describe (merge-pathnames "ASD.F" "LP:FOO;QWE;"))*
#P"LP:FOO;QWE;ASD.F.newest"
Type: LOGICAL-PATHNAME
Class: #<BUILT-IN-CLASS LOGICAL-PATHNAME>
TYPE: (LOGICAL-PATHNAME . #<CCL::CLASS-WRAPPER LOGICAL-PATHNAME
#x30004003C6ED>)
1: (:ABSOLUTE "FOO" "QWE")
2: "ASD"
3: "F"
%LOGICAL-PATHNAME-HOST: "LP"
%LOGICAL-PATHNAME-VERSION: :NEWEST
; No value

CL-USER> *(describe (merge-pathnames "" "LP:FOO;QWE;"))*
#P"LP:FOO;QWE;..newest"
Type: LOGICAL-PATHNAME
Class: #<BUILT-IN-CLASS LOGICAL-PATHNAME>
TYPE: (LOGICAL-PATHNAME . #<CCL::CLASS-WRAPPER LOGICAL-PATHNAME
#x30004003C6ED>)
1: (:ABSOLUTE "FOO" "QWE")
2: NIL
3: NIL
%LOGICAL-PATHNAME-HOST: "LP"
%LOGICAL-PATHNAME-VERSION: :NEWEST
; No value
CL-USER>


This is ECL (not very useful)

CL-USER> *(describe (merge-pathnames "ASD.F" "LP:FOO;QWE;"))*

#P"LP:FOO;QWE;ASD.F.NEWEST" - LOGICAL-PATHNAME
; No value
CL-USER> *(describe (merge-pathnames "" "LP:FOO;QWE;"))*

#P"LP:FOO;QWE;.NEWEST" - LOGICAL-PATHNAME
; No value
CL-USER>


This is SBCL

CL-USER> *(describe (merge-pathnames "ASD.F" "LP:FOO;QWE;"))*
#P"LP:ASD.F.NEWEST"
  [logical-pathname]

  HOST       = #<SB-KERNEL:LOGICAL-HOST "LP">
  DEVICE     = :UNSPECIFIC
  DIRECTORY  = (:ABSOLUTE)
  NAME       = "ASD"
  TYPE       = "F"
  VERSION    = :NEWEST
; No value

CL-USER> (*describe (merge-pathnames "" "LP:FOO;QWE;"))*
#<LOGICAL-PATHNAME (with no namestring)..
  [logical-pathname]

  HOST       = #<SB-KERNEL:LOGICAL-HOST "LP">
  DEVICE     = :UNSPECIFIC
  DIRECTORY  = (:ABSOLUTE)
  VERSION    = :NEWEST
; No value


... and finally, LWM

CL-USER 65 > *(describe (merge-pathnames "ASD.F" "LP:FOO;QWE;"))*

#P"LP:ASD.F.NEWEST" is a LOGICAL-PATHNAME
HOST           "LP"
DEVICE         :UNSPECIFIC
DIRECTORY      (:ABSOLUTE)
NAME           "ASD"
TYPE           "F"
VERSION        :NEWEST

CL-USER 68 > *(describe (merge-pathnames "" "LP:FOO;QWE;"))*

#P"LP:" is a LOGICAL-PATHNAME
HOST           "LP"
DEVICE         :UNSPECIFIC
DIRECTORY      (:ABSOLUTE)
NAME           NIL
TYPE           NIL
VERSION        :NEWEST

CLs are not logical, Spok.

MA






On Fri, Mar 13, 2026 at 8:50 PM Robert Goldman <[email protected]> wrote:

> Maybe call DESCRIBE on each of these so we can see what's in each one in
> full detail?
>
> On 13 Mar 2026, at 14:40, Marco Antoniotti (as marco dot antoniotti at
> unimib dot it) wrote:
>
> This is CCL
>
>
> CL-USER>
> *(setf (logical-pathname-translations "LP")                '(("**;*.*.*"
> "~/Projects/Foo/Bar/**/")))*
> (("**;*.*.*" "~/Projects/Foo/Bar/**/"))
> CL-USER> *(merge-pathnames "ASD.F" "LP:FOO;QWE;")*
> #P"LP:FOO;QWE;ASD.F.newest"
> CL-USER> *(merge-pathnames "" "LP:FOO;QWE;")*
> #P"LP:FOO;QWE;..newest"
> CL-USER>
>
>
> This is ECL
>
> CL-USER>
> *(setf (logical-pathname-translations "LP")                '(("**;*.*.*"
> "~/Projects/Foo/Bar/**/")))*
> ((#P"LP:**;*.*.*" #P"/Users/marcoxa/Projects/Foo/Bar/**/"))
> CL-USER>  *(merge-pathnames "ASD.F" "LP:FOO;QWE;")*
> #P"LP:FOO;QWE;ASD.F.NEWEST"
> CL-USER>  *(merge-pathnames "" "LP:FOO;QWE;")*
> #P"LP:FOO;QWE;.NEWEST"
> CL-USER>
>
> This is SBCL
>
> CL-USER>
> *(setf (logical-pathname-translations "LP")                '(("**;*.*.*"
> "~/Projects/Foo/Bar/**/")))*
> (("**;*.*.*" "~/Projects/Foo/Bar/**/"))
> CL-USER> *(merge-pathnames "ASD.F" "LP:FOO;QWE;")*
> #P"LP:ASD.F.NEWEST"
> CL-USER> *(merge-pathnames "" "LP:FOO;QWE;")*
> #<LOGICAL-PATHNAME (with no namestring)
>                    :HOST #<SB-KERNEL:LOGICAL-HOST "LP">
>                    :DEVICE :UNSPECIFIC
>                    :DIRECTORY (:ABSOLUTE)
>                    :NAME NIL
>                    :TYPE NIL
>                    :VERSION :NEWEST>
> CL-USER>
>
> This is LWM (same setup)
>
> CL-USER 61 > *(merge-pathnames "ASD.F" "LP:FOO;QWE;")*
> #P"LP:ASD.F.NEWEST"
>
> CL-USER 62 > *(merge-pathnames "" "LP:FOO;QWE;")*
> #P"LP:"
>
> CL-USER 63 >
>
> As you see there isn't much... logic in the results. 🙄
>
> Cheers
>
> MA
>
>
>
> On Fri, Mar 13, 2026 at 7:36 PM Martin Simmons <[email protected]>
> wrote:
>
>> It looks correct to me.  What are other CL's doing differently?
>>
>> --
>> Martin Simmons
>> LispWorks Ltd
>> http://www.lispworks.com/
>>
>>
>>
>> >>>>> On Wed, 11 Mar 2026 19:54:07 +0100, Marco Antoniotti (as marco dot
>> antoniotti at unimib dot it) said:
>> >
>> > Hi
>> >
>> > I have the following
>> >
>> > CL-USER 225 >
>> > (setf (logical-pathname-translations "LP")
>> > '(("**;*.*.*" "~/Projects/Foo/Bar/**/")))
>> > (("**;*.*.*" "~/Projects/Foo/Bar/**/"))
>> >
>> > Then
>> >
>> > CL-USER 256 > (merge-pathnames "ASD.F" "LP:FOO;QWE;")
>> > #P"LP:ASD.F.NEWEST"
>> >
>> > Which is ... different from what other CL's do.
>> >
>> > Any hermeneutics about this in LW?
>> >
>> > Cheers
>> > MA
>> >
>> >
>> > --
>> > Marco Antoniotti, Professor, Director         tel. +39 - 02 64 48 79 01
>> > DISCo, University of Milan-Bicocca U14 2043
>> http://dcb.disco.unimib.it
>> > Viale Sarca 336
>> > I-20126 Milan (MI) ITALY
>> >
>> > REGAINS: https://regains.disco.unimib.it/
>> >
>>
>
>
> --
> Marco Antoniotti, Professor, Director         tel. +39 - 02 64 48 79 01
> DISCo, University of Milan-Bicocca U14 2043   http://dcb.disco.unimib.it
> Viale Sarca 336
> I-20126 Milan (MI) ITALY
>
> REGAINS: https://regains.disco.unimib.it/
>
>

-- 
Marco Antoniotti, Professor, Director         tel. +39 - 02 64 48 79 01
DISCo, University of Milan-Bicocca U14 2043   http://dcb.disco.unimib.it
Viale Sarca 336
I-20126 Milan (MI) ITALY

REGAINS: https://regains.disco.unimib.it/