Custom Query (1030 matches)

Dan Weinreb 2009-09-08 15:09:04 EDT

delete-package, when called on a name that does not name a package, should return nil according to the Common Lisp hyperspec rather than signal a condition (for better or worse). Instead, it signals.

Comment 1 Ethan H. Schwartz 2009-09-10 17:22:03 EDT

from ​http://www.lispworks.com/documentation/HyperSpec/Body/f_del_pk.htm#delete-package:

Exceptional Situations:

If the package designator is a name that does not currently name a package, a correctable error of type package-error is signaled. If correction is attempted, no deletion action is attempted; instead, delete-package immediately returns nil.

[NB1: there are other exceptional situations in the CLHS]

[NB2: this was ITA bug 67561]

Dan Weinreb 2010-05-07 16:29:48 EDT

In a case such as this:

(defun foo (x y)
  (handler-case
      (/ x y)
    ((error serious-condition) ()
      5)))

it would be nice if the compiler could detect that (error serious-condition) is not a valid type (i.e. the programmer omitted the "or").

In

(defun bar (x)
  (check-type x (error serious-condition))
  x)

the compiler does, correctly, issue a warning; could that same mechanism be applied to handler-case?

NB: This was ITA bug 79938.

Mark Nahabedian 2010-05-24 09:33:02 EDT

There are a variety of cases where CCL signals nothing more specific than SIMPLE-ERROR. It would be helpful if appropriate conditions were defined for each of these cases and those conditions were signaled.

Here's an example of a case of SIMPLE-ERROR that should be something like NO-APPLICABLE-METHOD-ERROR instead:

There is no applicable method for the generic function:
  #<STANDARD-GENERIC-FUNCTION QRES-CORE:DO-LOAD-DB-RECORD-FROM-QAPI-OBJECT
#x3000434D4C2F>
when called with arguments:
  (QRES-CORE:QAPI-PNR-SEGMENT NIL :PARENTS (#<QAPI-PNR #<LEGACY-PNR
12474990031128/M/0 AC:PZCCLE,AC:PZCCLE #x300062B32F8D> :CHANGE-TOKEN: NIL>))

NB: Was ITA bug 80692