Can priority of interpreter-mode-alist over auto-mode-alist be changed?

Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[skuhagen]

Hello all

Sorry for posting twice (here and comp.emacs), I wasn't aware of this
group...


I have a very annoying problem with auto-mode. When editing Tcl-
Files,
 which often start with

#!/bin/sh
 #\
 exec tclsh "$0" "$@"

Emacs goes into shell-script-mode instead of Tcl-mode, although the
 filename ends with .tcl.
 As far as I understand the documentation, the reason is, that
 interpreter-mode-alist is searched
 for the interpreter given in the first line, and if one is found,
the
 mode-setting from the filename
 is ignored. I don't want to change interpreter-mode-alist, but I
want
 to have the mode by filename
 have priority over mode by first line of file. Is this possible?

TIA, regards
 Stephan

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Peter Dyballa]

Am 27.03.2008 um 13:42 schrieb skuhagen:
> #!/bin/sh
>  #\
>  exec tclsh "$0" "$@"

Why can't you use

	#!/bin/tclsh

directly?

--
Mit friedvollen Grüßen

   Pete

Der Langsamste, der sein Ziel nicht aus den Augen verliert, geht noch  
immer geschwinder als jener, der ohne Ziel umherirrt.

                       Gotthold Ephraim Lessing

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Lowell Gilbert]

Peter Dyballa <Peter_Dyballa@Web.DE> writes:

> Am 27.03.2008 um 13:42 schrieb skuhagen:
>> #!/bin/sh
>>  #\
>>  exec tclsh "$0" "$@"
>
> Why can't you use
>
> 	#!/bin/tclsh
>
> directly?

In some cases, because the script has to be run on multiple machines
that have different paths to tclsh.

I've used "Local Variables" sections to solve that in the past.
I wouldn't be surprised if there is a better way these days.

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Will Parsons]

Lowell Gilbert wrote:
> Peter Dyballa <Peter_Dyballa@Web.DE> writes:
>
>> Am 27.03.2008 um 13:42 schrieb skuhagen:
>>> #!/bin/sh
>>>  #\
>>>  exec tclsh "$0" "$@"
>>
>> Why can't you use
>>
>> 	#!/bin/tclsh
>>
>> directly?
>
> In some cases, because the script has to be run on multiple machines
> that have different paths to tclsh.

> I've used "Local Variables" sections to solve that in the past.
> I wouldn't be surprised if there is a better way these days.

This seems to be a regression with Emacs 22.  I, too, have tcl scripts
which begin with the common Tcl idiom cited by the OP, and they are
correctly recognized as tcl mode in Emacs 21 but shell mode in Emacs 22.

So, I'd like to join the OP in asking how to get the original behaviour
back?

-- 
Will

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Lennart Borgman (gmail)]

Will Parsons wrote:
> Lowell Gilbert wrote:
>> Peter Dyballa <Peter_Dyballa@Web.DE> writes:
>>
>>> Am 27.03.2008 um 13:42 schrieb skuhagen:
>>>> #!/bin/sh
>>>>  #\
>>>>  exec tclsh "$0" "$@"
>>> Why can't you use
>>>
>>> 	#!/bin/tclsh
>>>
>>> directly?
>> In some cases, because the script has to be run on multiple machines
>> that have different paths to tclsh.
> 
>> I've used "Local Variables" sections to solve that in the past.
>> I wouldn't be surprised if there is a better way these days.
> 
> This seems to be a regression with Emacs 22.  I, too, have tcl scripts
> which begin with the common Tcl idiom cited by the OP, and they are
> correctly recognized as tcl mode in Emacs 21 but shell mode in Emacs 22.
> 
> So, I'd like to join the OP in asking how to get the original behaviour
> back?

Did you look at the documentation?

   (info "(emacs) Choosing Modes")

It this clear? Can you do what you want?

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Peter Dyballa]

Am 28.03.2008 um 16:37 schrieb Will Parsons:
> So, I'd like to join the OP in asking how to get the original  
> behaviour
> back?


Send a bug report: Help menu -> Send Bug Report...

--
Greetings

   Pete

Isn't vi that text editor with two modes... one that beeps and one  
that corrupts your file?
				– Dan Jacobson, on comp.os.linux.advocacy

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Lowell Gilbert]

Will Parsons <wbp@nodomain.invalid> writes:

> Lowell Gilbert wrote:
>> Peter Dyballa <Peter_Dyballa@Web.DE> writes:
>>
>>> Am 27.03.2008 um 13:42 schrieb skuhagen:
>>>> #!/bin/sh
>>>>  #\
>>>>  exec tclsh "$0" "$@"
>>>
>>> Why can't you use
>>>
>>> 	#!/bin/tclsh
>>>
>>> directly?
>>
>> In some cases, because the script has to be run on multiple machines
>> that have different paths to tclsh.
>
>> I've used "Local Variables" sections to solve that in the past.
>> I wouldn't be surprised if there is a better way these days.
>
> This seems to be a regression with Emacs 22.  I, too, have tcl scripts
> which begin with the common Tcl idiom cited by the OP, and they are
> correctly recognized as tcl mode in Emacs 21 but shell mode in Emacs 22.
>
> So, I'd like to join the OP in asking how to get the original behaviour
> back?

Three minutes of investigation led me to think that you're looking for
the variable "magic-mode-alist".  

I think that what's happening is that your scripts end in ".tcl" and
the way it used to work was that auto-mode-alist used tcl-mode because
of the filename.  [If the scripts don't end in .tcl, I don't see how
it ever worked without a hint inside the file.]  Now something is
overriding auto-mode-alist, and it might be the "magic" mode-guessing.

There are other possibilities, but the ones I thought to check don't
seem to have changed lately.  [e.g., interpeter-mode-alist]

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Will Parsons]

Lowell Gilbert wrote:
> Will Parsons <wbp@nodomain.invalid> writes:
>
>> Lowell Gilbert wrote:
>>> Peter Dyballa <Peter_Dyballa@Web.DE> writes:
>>>
>>>> Am 27.03.2008 um 13:42 schrieb skuhagen:
>>>>> #!/bin/sh
>>>>>  #\
>>>>>  exec tclsh "$0" "$@"
>>>>
>>>> Why can't you use
>>>>
>>>> 	#!/bin/tclsh
>>>>
>>>> directly?
>>>
>>> In some cases, because the script has to be run on multiple machines
>>> that have different paths to tclsh.
>>
>>> I've used "Local Variables" sections to solve that in the past.
>>> I wouldn't be surprised if there is a better way these days.
>>
>> This seems to be a regression with Emacs 22.  I, too, have tcl scripts
>> which begin with the common Tcl idiom cited by the OP, and they are
>> correctly recognized as tcl mode in Emacs 21 but shell mode in Emacs 22.
>>
>> So, I'd like to join the OP in asking how to get the original behaviour
>> back?
>
> Three minutes of investigation led me to think that you're looking for
> the variable "magic-mode-alist".  

Perhaps it is, but if so, after reading the description of the variable I
am left with no idea of how to use it to get the desired effect.

> I think that what's happening is that your scripts end in ".tcl" and
> the way it used to work was that auto-mode-alist used tcl-mode because
> of the filename.  [If the scripts don't end in .tcl, I don't see how
> it ever worked without a hint inside the file.]  Now something is
> overriding auto-mode-alist, and it might be the "magic" mode-guessing.

Quite right.  For scripts that don't end in ".tcl", it would unrealistic to
expect that Emacs should know that a file with a "#!/bin/sh" shebang is
really a Tcl script, and in fact I add a second line in this case
containing "#-*-tcl-*" and that forces Tcl mode.  (So the question for me,
at least, is not how to force Tcl mode, but how to get the old behaviour
where Tcl mode is automatically recognized when Emacs should be able to do
so.)

> There are other possibilities, but the ones I thought to check don't
> seem to have changed lately.  [e.g., interpeter-mode-alist]

If this seems to be a bug, I'll file a bug report, unless someone can say
that this is an intended change and give an easy way of reverting to the
Emacs 21 behaviour.

-- 
Will

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Kevin Rodgers]

Will Parsons wrote:
> Lowell Gilbert wrote:
>> Will Parsons <wbp@nodomain.invalid> writes:
>>
>>> Lowell Gilbert wrote:
>>>> Peter Dyballa <Peter_Dyballa@Web.DE> writes:
>>>>
>>>>> Am 27.03.2008 um 13:42 schrieb skuhagen:
>>>>>> #!/bin/sh
>>>>>>  #\
>>>>>>  exec tclsh "$0" "$@"
>>>>> Why can't you use
>>>>>
>>>>> 	#!/bin/tclsh
>>>>>
>>>>> directly?
>>>> In some cases, because the script has to be run on multiple machines
>>>> that have different paths to tclsh.
>>>> I've used "Local Variables" sections to solve that in the past.
>>>> I wouldn't be surprised if there is a better way these days.
>>> This seems to be a regression with Emacs 22.  I, too, have tcl scripts
>>> which begin with the common Tcl idiom cited by the OP, and they are
>>> correctly recognized as tcl mode in Emacs 21 but shell mode in Emacs 22.
>>>
>>> So, I'd like to join the OP in asking how to get the original behaviour
>>> back?
>> Three minutes of investigation led me to think that you're looking for
>> the variable "magic-mode-alist".  
> 
> Perhaps it is, but if so, after reading the description of the variable I
> am left with no idea of how to use it to get the desired effect.

How about:

(add-to-list 'magic-mode-alist
	     (cons (regexp-quote "#\\\nexec tclsh \"$0\" \"$@\"")
		   'tcl-mode))

-- 
Kevin Rodgers
Denver, Colorado, USA

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Tim X]

Peter Dyballa <Peter_Dyballa@Web.DE> writes:

> Am 27.03.2008 um 13:42 schrieb skuhagen:
>> #!/bin/sh
>>  #\
>>  exec tclsh "$0" "$@"
>
> Why can't you use
>
> 	#!/bin/tclsh
>

The way the OP wants to call the script is how Tcl and other scripting
languages recommend doing it. This avoids having to hard code the tcl
path in the script - for example, if a preferred and newer version of
tcl was in /usr/local/bin, the OPs preferred method would find that over
an older version in /usr/bin/tcl. Essentially, it is a way of avoiding
explicit paths to interpreters in the script, makinig it more portable
and giving greater flexibility.

Tim

-- 
tcross (at) rapttech dot com dot au

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Peter Dyballa]

Am 29.03.2008 um 05:51 schrieb Tim X:
> The way the OP wants to call the script is how Tcl and other scripting
> languages recommend doing it. This avoids having to hard code the tcl
> path in the script


This could be achieved the way it's done with Perl scripts

	:
	eval 'exec perl -w -S $0 ${1+"$@"}'

The first line allows to use

	# -*- perl -*-

or

	# -*- tcl -*-

to evoke the proper mood in GNU Emacs ...

--
Greetings

   Pete

Upgraded, adj.:
	Didn't work the first time.

Re: Can priority of interpreter-mode-alist over auto-mode-alist be changed?

[Will Parsons]

Peter Dyballa wrote:
>
> Am 29.03.2008 um 05:51 schrieb Tim X:
>> The way the OP wants to call the script is how Tcl and other scripting
>> languages recommend doing it. This avoids having to hard code the tcl
>> path in the script
>
> This could be achieved the way it's done with Perl scripts
>
> 	:
> 	eval 'exec perl -w -S $0 ${1+"$@"}'

There's no need introduce eval - the lines
   #\
   exec tclsh "$0" ${1+"$@"}
serve to invoke tclsh.

> The first line allows to use
>
> 	# -*- perl -*-
>
> or
>
> 	# -*- tcl -*-
>
> to evoke the proper mood in GNU Emacs ...

Yes, of course - but the fact remains that it shouldn't be necessary to do
this, and in fact it wasn't under Emacs 21.

-- 
Will