two likely bugs with qualified methods

two likely bugs with qualified methods

[Eric Abrahamsen]

Not serious ones, but...

See the following:

(cl-defmethod base ((str string))
  "This one's okay"
  (message str))

(cl-defmethod base :extra "ext" ((str string))
	      "This one isn't"
	      (message "extra method")
	      (cl-call-next-method))

The first problem should be evident: alignment doesn't work correctly
for any qualified methods. This is with emacs -Q, built from master.

Additionally, if you try to instrument the second form for edbugging,
the cursor jumps to the first argument in the argument list, and you
get:

edebug-syntax-error: Invalid read syntax: "Expected lambda expression"

That only happens with the :extra qualifier (I assume because it has an
additional positional element before the arg list).

Both of these are pretty much just chrome, but they're fairly important
chrome! I will open a couple of bug reports, if necessary.

Thanks,
Eric

Re: two likely bugs with qualified methods

[Clément Pit--Claudel]

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On 2016-07-15 09:11, Eric Abrahamsen wrote:
> Not serious ones, but...
> 
> See the following:
> 
> (cl-defmethod base ((str string))
>   "This one's okay"
>   (message str))
> 
> (cl-defmethod base :extra "ext" ((str string))
> 	      "This one isn't"
> 	      (message "extra method")
> 	      (cl-call-next-method))
> 
> The first problem should be evident: alignment doesn't work correctly
> for any qualified methods. This is with emacs -Q, built from master.
> 
> Additionally, if you try to instrument the second form for edbugging,
> the cursor jumps to the first argument in the argument list, and you
> get:
> 
> edebug-syntax-error: Invalid read syntax: "Expected lambda expression"

Both problems can probably be fixed by adjusting the (declare) form at the beginning of cl-defmethod:

  (declare (doc-string 3) (indent 2)
           (debug
            (&define                    ; this means we are defining something
             [&or name ("setf" :name setf name)]
             ;; ^^ This is the methods symbol
             [ &optional keywordp ]     ; this is key :before etc
             list                       ; arguments
             [ &optional stringp ]      ; documentation string
             def-body)))                ; part to be debugged

(indent 2) could be changed to (indent defun); the debug spec could probably be fixed by using one of the edebug specs in cl-macs, such as `cl-lambda-list'.

Clément.


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Re: two likely bugs with qualified methods

[Stefan Monnier]

>   (declare (doc-string 3) (indent 2)
>            (debug
>             (&define                    ; this means we are defining something
>              [&or name ("setf" :name setf name)]
>              ;; ^^ This is the methods symbol
>              [ &optional keywordp ]     ; this is key :before etc
>              list                       ; arguments
>              [ &optional stringp ]      ; documentation string
>              def-body)))                ; part to be debugged

> (indent 2) could be changed to (indent defun);

That might work, indeed.

>  the debug spec could probably be fixed by using one of the edebug
>  specs in cl-macs, such as `cl-lambda-list'.

I don't think this will help.  The problem is that the qualifiers are
matched by [ &optional keywordp ] which was sufficient for EIEIO's
defmethod, but not for cl-defmethod (which accepts the more general
Common Lisp form of qualifiers, i.e. any sequence of non-lists).


        Stefan

Re: two likely bugs with qualified methods

[Eric Abrahamsen]

Clément Pit--Claudel <clement.pit@gmail.com> writes:

> On 2016-07-15 09:11, Eric Abrahamsen wrote:
>> Not serious ones, but...
>> 
>> See the following:
>> 
>> (cl-defmethod base ((str string))
>>   "This one's okay"
>>   (message str))
>> 
>> (cl-defmethod base :extra "ext" ((str string))
>> 	      "This one isn't"
>> 	      (message "extra method")
>> 	      (cl-call-next-method))
>> 
>> The first problem should be evident: alignment doesn't work correctly
>> for any qualified methods. This is with emacs -Q, built from master.
>> 
>> Additionally, if you try to instrument the second form for edbugging,
>> the cursor jumps to the first argument in the argument list, and you
>> get:
>> 
>> edebug-syntax-error: Invalid read syntax: "Expected lambda expression"
>
> Both problems can probably be fixed by adjusting the (declare) form at the beginning of cl-defmethod:
>
>   (declare (doc-string 3) (indent 2)
>            (debug
>             (&define                    ; this means we are defining something
>              [&or name ("setf" :name setf name)]
>              ;; ^^ This is the methods symbol
>              [ &optional keywordp ]     ; this is key :before etc
>              list                       ; arguments
>              [ &optional stringp ]      ; documentation string
>              def-body)))                ; part to be debugged
>
> (indent 2) could be changed to (indent defun); the debug spec could
> probably be fixed by using one of the edebug specs in cl-macs, such as
> `cl-lambda-lis

I tried taking a whack at this before posting, but wasn't familiar
enough with declare to get it to work. Anyhow, there are now two bug
reports for this: 23994 and 23995.

E

Re: two likely bugs with qualified methods

[Stefan Monnier]

> Both of these are pretty much just chrome, but they're fairly important
> chrome! I will open a couple of bug reports, if necessary.

Yes, please open bug reports for these.  A related issue is that the
"ext" part of your :extra qualifier is highlighted as a docstring.


        Stefan