what is 'cl-user:: ?

From: budden
Subject: what is 'cl-user:: ?
Date: Sat, 25 Apr 2009 20:14:32 +0000
Message-ID: <149286e6-b0f9-4dd5-834e-f0ce6dc773da@y34g2000prb.googlegroups.com>

Hi!
> 'cl-user::
behaves differently. Some lisps return
cl-user::||
some err.
Which is correct behaviour?

Re: what is 'cl-user:: ? Pascal J. Bourguignon
- Re: what is 'cl-user:: ? budden
  - Re: what is 'cl-user:: ? Raffael Cavallaro
  - Re: what is 'cl-user:: ? Rob Warnock

From: Pascal J. Bourguignon
Subject: Re: what is 'cl-user:: ?
Date: Sat, 25 Apr 2009 20:22:58 +0000
Message-ID: <87ocukbhzx.fsf@galatea.local>

budden <···········@mail.ru> writes:

> Hi!
>> 'cl-user::
> behaves differently. Some lisps return
> cl-user::||
> some err.
> Which is correct behaviour?

The correct behavior is to avoid reading cl-user::


cl-user:: is not amongst the valid patterns for a token:
http://www.lispworks.com/documentation/HyperSpec/Body/02_ce.htm

-- 
__Pascal Bourguignon__

From: budden
Subject: Re: what is 'cl-user:: ?
Date: Sat, 25 Apr 2009 20:38:05 +0000
Message-ID: <633ba5b5-e8a2-4bc7-8a06-a127d902d8e2@r31g2000prh.googlegroups.com>

Thanks!
In a practice:

lispworks, clisp, ccl
(read-from-string "cl-user::")
returns cl-user::||

sbcl and allegro report a error.

From: Raffael Cavallaro
Subject: Re: what is 'cl-user:: ?
Date: Sun, 26 Apr 2009 00:05:34 +0000
Message-ID: <889ffd90-4b97-4610-9be3-499c09344b72@s1g2000prd.googlegroups.com>

On Apr 25, 4:38 pm, budden <···········@mail.ru> wrote:
> Thanks!
> In a practice:
>
> lispworks, clisp, ccl
> (read-from-string "cl-user::")
> returns cl-user::||
>
> sbcl and allegro report a error.

this must have been patched recently in ccl as it now returns:
> Error: Reader error: Illegal symbol syntax.

From: Rob Warnock
Subject: Re: what is 'cl-user:: ?
Date: Sun, 26 Apr 2009 03:28:06 +0000
Message-ID: <u_SdnXfM6MhbSW7UnZ2dnUVZ_o2dnZ2d@speakeasy.net>

budden  <···········@mail.ru> wrote:
+---------------
| In a practice:
| 
| lispworks, clisp, ccl
| (read-from-string "cl-user::")
| returns cl-user::||
| 
| sbcl and allegro report a error.
+---------------

As others have noted, bare CL-USER:: is an illegal token. However,
CL-USER::|| *is* a legal token, and thus the following should work
everywhere:

    > (read-from-string "cl-user::||")

    ||
    11
    > (eq * (intern "" "CL-USER"))

    T
    > (symbol-name **)

    ""
    > (length *)

    0
    > 


-Rob

-----
Rob Warnock			<····@rpw3.org>
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