[TxMt] tiny improvements for perlmate.rb

[Hans-Joerg Bibiko]

Hi Alex

On 30 Nov 2006, at 09:15, Alexander Ross wrote:

> I've just committed an improved PerlMate.  PerlMate now causes perl to
> load  exception_handler.pm before executing the user code.
> exception_handler.pm overrides CORE::GLOBAL::die to format unhandled
> exceptions and print them to the file descriptor given by the
> environment varibale TM_ERROR_FD.  This let's us manipulate the actual
> exception objects instead of just their string representations.
>
> The implementation is very basic, as I have no actual Perl programming
> experience.  But it handles `die "Sometext";` just fine.  I don't know
> how it will react to the throwing of except objects.

I just checked your exception handler. It works fine as long as you  
use 'die' mot in a 'eval' environment.
In Perl you often write your own handler like this:

Example:
_______________________
#!/usr/bin/perl -w

$a =  5;
$b = -1;

eval {
    $c = $a / $b;
    die "Denominator cannot be negative" if ($b < 0);
};

print "Run-time error: $@";
_________________________

If I run this the 'die' output never reaches your exception handler  
because of

if($^S) {
	CORE::die($@);
}...

Perl's $@ refers now to exception_handler.pm line 34 and this is not  
what I want to see.

Why did you choose this 'if clause' to call CORE::die?

If you leave it out and take only the else clause it works. (?)

On the other hand you have a small typo in line 55 of  
exception_handler.pm

corrected:
print TM_ERROR_FD '<tr><td>in <a href="txmt://open?' . $url .  
'&line=' . $line . '"> ' . $display_name . "</a> at line $line<td></ 
tr>\n" ;

because:

print '$line' will print "$line" not the content of the variable $line.


###########

I wrote a small error/warning formatter in my posted perlmate.rb.  
Would it better to use TM_ERROR_FD instead of

class PerlMate < ScriptMate
   def filter_stderr(str)
...
?

-Hans