March 2008 - cdr-discuss - mailman3.common-lisp.net

Re: [cdr-discuss] Three RFCs
by Edi Weitz 06 Apr '08

06 Apr '08

On Tue, 18 Mar 2008 12:36:47 +0100, Pascal Costanza <pc(a)p-cos.net> wrote: > ...but that's ambiguous: Only if you insist on having a short form without parentheses. That's not a hard-and-fast requirement. > (case (thing :test #'=) > (42 'foo) > (4711 'bar)) > > What's the result of that form? Error: The variable THING is unbound.

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[cdr-discuss] [RfC] Issue: INSPECTOR-HOOK
by Tobias C. Rittweiler 20 Mar '08

20 Mar '08

Request for comments (this includes stylistic / spelling corrections) -T. Status: Draft Forum: Common Lisp Document Repository (CDR) Issue: INSPECTOR-HOOK References: INSPECT (function), *DEBUGGER-HOOK* (variable) Category: Addition Edit History: 20-Mar-2008 by Rittweiler (Draft) Problem Description: Cross-implementation Lisp programming environments such as SLIME or Climacs face the problem that the ANSI Common Lisp standard does not specify any way to hook into the inspection machinery of an implementation. Specifically, there is no portable way to install an inspector that is run when the function INSPECT is invoked. Proposal (INSPECTOR-HOOK:*INSPECTOR-HOOK*-VARIABLE) Add a variable: *INSPECTOR-HOOK* [VARIABLE] Value Type: A designator for a function of one argument (the object to be inspected), or NIL. Initial Value: NIL. Description: When the value of *INSPECTOR-HOOK* is non-NIL, an invocation of INSPECT in the dynamic-extent of this variable results in calling the value with the object that was originally passed to INSPECT. *INSPECTOR-HOOK* is not rebound before calling the function denoted by the value, i.e. it's bound to the same value as at the invocation of INSPECT; this is to allow inspectors to be defined recursively. The return value of INSPECT is independent of the return value of the denoted function, and remains implementation-dependent. Affected By: INSPECT See Also: *DEBUGGER-HOOK* Notes: It's possible to invoke the implementation's inspection machinery from within *INSPECTOR-HOOK* by binding it to NIL before invoking INSPECT. Rationale: This proposal was closely modelled on the specification of *DEBUGGER-HOOK*, and allows programs to install their own inspectors that are adapted to their respective domains. Notes: The proposal does deliberately say nothing about the home-package of the symbol *INSPECTOR-HOOK*. However, implementors are encouraged to export this symbol from their extensions package (often called "EXT") or another appropriate package---unless a later CDR document specifies a more explicit location. Current Practise: On at least SBCL, Clisp, and Clozure CL, it's possible to straightforwardly hook into their inspection machinery, albeit by mostly unexported and undocumented means. The documentation of Franz' Allegro CL states that an invocation of INSPECT runs a GUI inspector on the MS Windows operating system, and a text-based inspector on other operating systems, so it's very likely that they employ some hook mechanism internally. Cost to implementators: Negligible. Cost to user: None. The proposal is fully upward compatible. Cost of Non-Adoption: The problem, as described above, remains. Benefits: Slightly more powerful / convenient Lisp programming environments. Aesthetics: Inhibits the necessity to rely on implementation-dependent cruft.

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[cdr-discuss] Three RFCs
by Leslie P. Polzer 18 Mar '08

18 Mar '08

Hello folks, here are three CDR ideas that I would like to get your comments on: 1. Support a :TEST arg for (E)CASE. 2. Setup BACKQUOTE to be the backquote expansion object. I believe this is common implementor's practice. 3. Support extended feature tests. It would be nice to be able to say +(find-package 'zoo)(...) The complexity impact is none for #2, probably neglectable for #3 and should be moderate for #1. Leslie

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[cdr-discuss] CDR5 in alexandria
by Attila Lendvai 01 Mar '08

01 Mar '08

dear list, fyi, alexandria now has an almost full implementation of CDR5: http://common-lisp.net/project/alexandria/ http://common-lisp.net/cgi-bin/darcsweb/darcsweb.cgi?r=alexandria-alexandri… -- attila ps: no testsuite yet, patches are welcome.

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[cdr-discuss] CDR 5
by Gary King 01 Mar '08

01 Mar '08

I haven't looked over all the details but this seems like a very good idea to me and also seems clear, to the point and precise. nice work, -- Gary Warren King, metabang.com Cell: (413) 559 8738 Fax: (206) 338-4052 gwkkwg on Skype * garethsan on AIM

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