Does not byte-compile return the compiled function in Emacs 24?

Does not byte-compile return the compiled function in Emacs 24?

[Lennart Borgman]

It used to do that before. Is there any variable holding the newly
byte-compiled function?

Re: Does not byte-compile return the compiled function in Emacs 24?

[Juanma Barranquero]

> It used to do that before.

It wasn't documented, was it?

> Is there any variable holding the newly
> byte-compiled function?

A function, as before:

(symbol-function 'my-func)

    Juanma

Re: Does not byte-compile return the compiled function in Emacs 24?

[Stefan Monnier]

> It used to do that before. Is there any variable holding the newly
> byte-compiled function?

Don't know.  `byte-compile' does various things in various circumstances
(it's pretty DWIMish), so without more details I can't help you.


        Stefan

Re: Does not byte-compile return the compiled function in Emacs 24?

[Lennart Borgman]

On Wed, Dec 7, 2011 at 02:36, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>> It used to do that before. Is there any variable holding the newly
>> byte-compiled function?
>
> Don't know.  `byte-compile' does various things in various circumstances
> (it's pretty DWIMish), so without more details I can't help you.

In mumamo.el I am building functions for fontification. I compile them
like this:

        (setq byte-compiled-fun (let ((major-syntax-table))
                                  (byte-compile fetch-func-definition)))

Previously it returned the byte-compiled function, but now it seems to
return t. (Or, at least it did not when I tested.)

I am using an anonymous function, but I think I can switch to a named
temporary function instead. I will try that.

Re: Does not byte-compile return the compiled function in Emacs 24?

[Kevin Rodgers]

On 12/6/11 5:51 PM, Juanma Barranquero wrote:
>> It used to do that before.
>
> It wasn't documented, was it?

It is the obvious, sensible value to return.

>> Is there any variable holding the newly
>> byte-compiled function?
>
> A function, as before:
>
> (symbol-function 'my-func)

As Lennart points out, that does not cover lambda forms.

-- 
Kevin Rodgers
Denver, Colorado, USA

Re: Does not byte-compile return the compiled function in Emacs 24?

[Lennart Borgman]

On Wed, Dec 7, 2011 at 05:24, Kevin Rodgers <kevin.d.rodgers@gmail.com> wrote:
> On 12/6/11 5:51 PM, Juanma Barranquero wrote:
>>>
>>> It used to do that before.
>>
>>
>> It wasn't documented, was it?
>
>
> It is the obvious, sensible value to return.
>
>
>>> Is there any variable holding the newly
>>> byte-compiled function?
>>
>>
>> A function, as before:
>>
>> (symbol-function 'my-func)
>
>
> As Lennart points out, that does not cover lambda forms.

I agree with Kevin, of course.

I just tried adding a name:

   (byte-compile '(defun my-name () ...))

To my surprise the symbol my-name is not a function after this.

Re: Does not byte-compile return the compiled function in Emacs 24?

[Kevin Rodgers]

On Tue, Dec 6, 2011 at 9:38 PM, Lennart Borgman
<lennart.borgman@gmail.com> wrote:
> I just tried adding a name:
>
>   (byte-compile '(defun my-name () ...))
>
> To my surprise the symbol my-name is not a function after this.

Shouldn't that be (without the quote):

(byte-compile (defun my-name () ...))

-- 
Kevin Rodgers
Denver, Colorado, USA

Re: Does not byte-compile return the compiled function in Emacs 24?

[Andreas Schwab]

Lennart Borgman <lennart.borgman@gmail.com> writes:

> In mumamo.el I am building functions for fontification. I compile them
> like this:
>
>         (setq byte-compiled-fun (let ((major-syntax-table))
>                                   (byte-compile fetch-func-definition)))
>
> Previously it returned the byte-compiled function, but now it seems to
> return t. (Or, at least it did not when I tested.)

Works for me.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Does not byte-compile return the compiled function in Emacs 24?

[Stefan Monnier]

>>> It used to do that before. Is there any variable holding the newly
>>> byte-compiled function?
>> Don't know.  `byte-compile' does various things in various circumstances
>> (it's pretty DWIMish), so without more details I can't help you.
> In mumamo.el I am building functions for fontification. I compile them
> like this:
>         (setq byte-compiled-fun (let ((major-syntax-table))
>                                   (byte-compile fetch-func-definition)))

This just tells me you call the function with some value and the get
the result.  I.e. not much more information.
The key is to know what kind of value is passed to byte-compile: is it
a symbol, an arbitrary Lisp expression, a lambda expression, ...

> Previously it returned the byte-compiled function, but now it seems to
> return t. (Or, at least it did not when I tested.)

   ELISP> (byte-compile '(lambda (x) (+ x 1)))
   #[(x)
     "\bT\207"
     [x]
     1]
   
   ELISP> 

> I am using an anonymous function, but I think I can switch to a named
> temporary function instead. I will try that.

If it's a lambda expression, I can't reproduce the problem, as
shown above.
BTW, C-u C-M-x in byte-compile and then single-stepping in this function
should quickly tell you the reason for what you see (unless there's
some defadvice at play, of course).


        Stefan

Re: Does not byte-compile return the compiled function in Emacs 24?

[Lennart Borgman]

On Wed, Dec 7, 2011 at 16:12, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>>>> It used to do that before. Is there any variable holding the newly
>>>> byte-compiled function?
>>> Don't know.  `byte-compile' does various things in various circumstances
>>> (it's pretty DWIMish), so without more details I can't help you.
>> In mumamo.el I am building functions for fontification. I compile them
>> like this:
>>         (setq byte-compiled-fun (let ((major-syntax-table))
>>                                   (byte-compile fetch-func-definition)))
>
> This just tells me you call the function with some value and the get
> the result.  I.e. not much more information.
> The key is to know what kind of value is passed to byte-compile: is it
> a symbol, an arbitrary Lisp expression, a lambda expression, ...

It is a lisp expression, but a big one. I am building a function to
call before fontification. This function let binds relevant variables
for the fontification.

When testing a bit more I see that (byte-compile (lambda ...)) returns
the function when everything goes ok, but not when there is an error.
For the function for php-mode fontification I get an error during byte
compilation:

  Error: Wrong type argument: number-or-marker-p, nil

So it looks like byte-compile dislikes something in the (lambda ...)
for php-mode fontification. I just wished I knew what it is... ;-)

Perhaps someone has an idea of how to catch it? I build the let-list
with entries like

      (list 'font-lock-syntactic-face-function (custom-quote
font-lock-syntactic-face-function))

Could this go wrong for some values?

Re: Does not byte-compile return the compiled function in Emacs 24?

[Johan Bockgård]

Stefan Monnier <monnier@IRO.UMontreal.CA> writes:

> Don't know.  `byte-compile' does various things in various circumstances
> (it's pretty DWIMish), so without more details I can't help you.

What about this?

  (byte-compile (defun foo ()))   => #[...]
  (byte-compile (lambda () nil))  => #[...]

  (setq lexical-binding t)

  (byte-compile (defun foo ()))   => nil
  (byte-compile (lambda () nil))  => nil

Re: Does not byte-compile return the compiled function in Emacs 24?

[Stefan Monnier]

>> Don't know.  `byte-compile' does various things in various circumstances
>> (it's pretty DWIMish), so without more details I can't help you.

> What about this?

>   (byte-compile (defun foo ()))   => #[...]

This is really:

   (defun foo ())
   (byte-compile 'foo)

>   (byte-compile (lambda () nil))  => #[...]

This happens to be the same as

   (byte-compile '(lambda () nil))

which is the preferred form to call it.
   
>   (setq lexical-binding t)
>   (byte-compile (defun foo ()))   => nil

Indeed, this is not supported currently: (symbol-function 'foo) is
a closure rather than a lambda expression, and byte-compile doesn't know
how to compile a closure.

>   (byte-compile (lambda () nil))  => nil

This fails because you're passing it a closure rather than
a lambda-expression (i.e. same problem as for `defun' above).

This works: (byte-compile '(lambda () nil))


        Stefan

Re: Does not byte-compile return the compiled function in Emacs 24?

[Lennart Borgman]

On Wed, Dec 7, 2011 at 17:34, Lennart Borgman <lennart.borgman@gmail.com> wrote:
>>> In mumamo.el I am building functions for fontification. I compile them
>>> like this:
>>>         (setq byte-compiled-fun (let ((major-syntax-table))
>>>                                   (byte-compile fetch-func-definition)))
>>
>> This just tells me you call the function with some value and the get
>> the result.  I.e. not much more information.
>> The key is to know what kind of value is passed to byte-compile: is it
>> a symbol, an arbitrary Lisp expression, a lambda expression, ...
>
> It is a lisp expression, but a big one. I am building a function to
> call before fontification. This function let binds relevant variables
> for the fontification.
>
> When testing a bit more I see that (byte-compile (lambda ...)) returns
> the function when everything goes ok, but not when there is an error.
> For the function for php-mode fontification I get an error during byte
> compilation:
>
>  Error: Wrong type argument: number-or-marker-p, nil
>
> So it looks like byte-compile dislikes something in the (lambda ...)
> for php-mode fontification. I just wished I knew what it is... ;-)

I am beginning to think that it is the size of the code for the
(lambda ...) that is the problem. When I delete some lines at least
byte-compile returns the function and I do not get the error above.

The size of the text code is some 230 000 characters (including white
space). The reason that it is so big is probably the syntax tables
copied, like this for example:

    (list 'font-lock-syntax-table (custom-quote font-lock-syntax-table))

Including this in some way was necessary for fontification: ;; See
nXhtml bug 400415

Perhaps I should just make a local copy of the syntax table instead... hm...

That requires a bit of work. There are some more syntax tables too.
Any thoughts or ideas on this?

Re: Does not byte-compile return the compiled function in Emacs 24?

[Stefan Monnier]

> Any thoughts or ideas on this?

My thoughts on this revolve around "what the @#$ is he talking about?".


        Stefan