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From: xach@xach.com To: wlclive@live.com CC: armedbear-devel@common-lisp.net Subject: Re: [armedbear-devel] Package redefinition issue in REPL. Date: Wed, 25 Apr 2012 07:01:07 -0400
wl chiu wlclive@live.com writes:
Hello dear developers,
I' just experienced an odd issue with defpackage. It looked like the package will not be modified if I call defpackage again.
For example, I define a package called "a-package". After a while I wanted to export a function that I've just implemented called "a-new-foo". Naturally I would add a new entry under the :export section of defpackage, and then eval the expression again. However, I still cannot access "a-new-foo" as the REPL gives me "such symbol is not external of package [a-package]" error message.
Please advice and many thanks,
I don't know what the intent of ABCL is, but this behavior is allowed by the specification of DEFPACKAGE:
If defined-package-name already refers to an existing package, the name-to-package mapping for that name is not changed. If the new definition is at variance with the current state of that package, the consequences are undefined; an implementation might choose to modify the existing package to reflect the new definition.
You can modify the export status of a symbol reliably at runtime with the EXPORT function.
Zach
Thank you very much! I guess for now I have to rely on the function "export" during the development. I do hope one day the modification behavior will be implemented :) Best regards, Wei-Lun Chiu