compile perl file, specify current buffer, using help effectively

compile perl file, specify current buffer, using help effectively

[David Schneider]

I am trying to use emacs as an IDE for perl development.  I think it
would be useful to have a compile command that runs perl on the
current buffer I am editing.  The compile command defaults to make -k.
 I want to change it to perl xx where xx is the name of the current
buffer - is there some variable or special syntax I can use to get the
current filename?  More important then the answer, is how do I figure
this out from the help.  I have been using C-h a to try to search the
help.  This gives me lists of commands or variables which may be
related - but I frequently find my questions are still unanswered.

Re: compile perl file, specify current buffer, using help effectively

[Eli Zaretskii]

> Date: Tue, 2 May 2006 22:04:56 -0400
> From: "David Schneider" <goedelsch@gmail.com>
> 
> More important then the answer, is how do I figure this out from the
> help.

Using the index search of the Emacs manual is one of the most
efficient and powerful ways.  Get to the Emacs manual (by typing
"C-h i" then "m Emacs RET", or select the Emacs manual from the
menu-bar's "Help" menu), then type "i TOPIC RET", where TOPIC is any
word or phrase that seems to be related to what you are looking for,
and Emacs will land you on the place in the manual where that topic is
discussed.

In this case, "i compile RET" lands me in a section where I find this
paragraph:

       The default for the compilation command is normally `make -k', which
    is correct most of the time for nontrivial programs.  (*Note Make:
    (make)Top.)  If you have done `M-x compile' before, the default each
    time is the command you used the previous time.  `compile' stores this
    command in the variable `compile-command', so setting that variable
    specifies the default for the next use of `M-x compile'.  If a file
    specifies a file local value for `compile-command', that provides the
    default when you type `M-x compile' in that file's buffer.  *Note File
    Variables::.

Would this paragraph tell you what you wanted to know?

Re: compile perl file, specify current buffer, using help effectively

[David Hansen]

On Tue, 2 May 2006 22:04:56 -0400 David Schneider wrote:

> I am trying to use emacs as an IDE for perl development.  I think it
> would be useful to have a compile command that runs perl on the
> current buffer I am editing.  The compile command defaults to make -k.
> I want to change it to perl xx where xx is the name of the current
> buffer - is there some variable or special syntax I can use to get the
> current filename?  More important then the answer, is how do I figure
> this out from the help.  I have been using C-h a to try to search the
> help.  This gives me lists of commands or variables which may be
> related - but I frequently find my questions are still unanswered.

Not tested:

(add-hook 'perl-mode-hook
          (lambda ()
            (set (make-local-variable 'compile-command)
                 (concat "perl -w " (buffer-file-name)))))

Anyway i doub't that the compile mode will recognize the
perl errors and warnings.

David

Re: compile perl file, specify current buffer, using help effectively

[Kevin Rodgers]

David Hansen wrote:
> On Tue, 2 May 2006 22:04:56 -0400 David Schneider wrote:
>> I am trying to use emacs as an IDE for perl development.  I think it
>> would be useful to have a compile command that runs perl on the
>> current buffer I am editing.  The compile command defaults to make -k.
>> I want to change it to perl xx where xx is the name of the current
>> buffer - is there some variable or special syntax I can use to get the
>> current filename?  More important then the answer, is how do I figure
>> this out from the help.  I have been using C-h a to try to search the
>> help.  This gives me lists of commands or variables which may be
>> related - but I frequently find my questions are still unanswered.

`C-h a' is for commands.  `C-h f' is for functions.  `C-h v' is for
variables.

`C-h v compile-command' has a C mode example that David has converted
to Perl mode for you:

> Not tested:
> 
> (add-hook 'perl-mode-hook
>           (lambda ()
>             (set (make-local-variable 'compile-command)
>                  (concat "perl -w " (buffer-file-name)))))
> 
> Anyway i doub't that the compile mode will recognize the
> perl errors and warnings.

See compilation-error-regexp-alist:

     ;; Perl -w:
     ;; syntax error at automake line 922, near "':'"
     ;; Perl debugging traces
     ;; store::odrecall('File_A', 'x2') called at store.pm line 90
     (".* at \\([^ \n]+\\) line \\([0-9]+\\)[,.\n]" 1 2)

-- 
Kevin

Re: compile perl file, specify current buffer, using help effectively

[Stefan Monnier]

> I am trying to use emacs as an IDE for perl development.  I think it
> would be useful to have a compile command that runs perl on the
> current buffer I am editing.  The compile command defaults to make -k.
> I want to change it to perl xx where xx is the name of the current
> buffer - is there some variable or special syntax I can use to get the
> current filename?  More important then the answer, is how do I figure
> this out from the help.

Try C-h f compile RET (which will give you the online doc about the
`compile' command).  It comes with an example of exactly what you want
to do.


        Stefan

Re: compile perl file, specify current buffer, using help effectively

[Burton Samograd]

"David Schneider" <goedelsch@gmail.com> writes:

> I am trying to use emacs as an IDE for perl development.  I think it
> would be useful to have a compile command that runs perl on the
> current buffer I am editing.  The compile command defaults to make -k.
> I want to change it to perl xx where xx is the name of the current
> buffer - is there some variable or special syntax I can use to get the
> current filename?

In your ~/.emacs you can put:

(setq compile-command "perl xx")

or you can just change the command name when it asks and then it will
use whatever you set it to for subsiquent compiles.

A handy binding in your .emacs is:

(global-set-key "\C-cc" 'compile)

Which calls compile when you hit Control c and then c.
  
> More important then the answer, is how do I figure
> this out from the help.  I have been using C-h a to try to search the
> help.  This gives me lists of commands or variables which may be
> related - but I frequently find my questions are still unanswered.

That is just something that takes time to learn.  Emacs is big and
takes a *long* time to master.  Asking questions (like you are doing)
is one of the best ways to get quick answers.  You can then learn more
by taking the answer and exploring emacs more.  Try looking at the
compile-command variable documentation using C-h v
(describe-variable). Another useful one is C-h f (describe-function),
which you can use to describe the compile function (where you can find
out about the compile-command variable, 5th paragraph).

-- 
burton samograd					kruhft .at. gmail
kruhft.blogspot.com	www.myspace.com/kruhft	metashell.blogspot.com

Re: compile perl file, specify current buffer, using help effectively

[yoorobot]

this may be anathema, but  I use viper-mode when I am editing *code*
(including perl) and so I can use the vi/vim style command mode:

<ESC>:!perl %

executes a shell program and feeds the current buffer as input.

- James