[ic] interchange and external perl packages

[Mike Heins]

Quoting David McGuire (dmcguire@bresystems.com):
> I'm trying to build a UserTag that has to use an external library.  I'm not
> all that familiar with interchange as of yet being that I just got moved
> into this project, but here's what I've written so far:
> 
> UserTag thumb Order path
> UserTag thumb PosNumber 1
> UserTag thumb Routine <<EOR
> eval {
>     require Image::Magick;
> };
> if($@) {
>         return sub {
>             ::logError("Cannot generate thumbnail, Image::Magick module not
> installed: $@");
>         };
> }
> use Image::Magick;
> sub {
>        my ($path) = @ ;
>        my $srcImage = Image::Magick->new;
>        my $x = $srcImage->Read($path);
>        $x = $srcImage->Resize(geometry=>'100x100');
>        $x = $srcImage->Write($path);
>        return;
> }
> EOR
> 
> the "use Image::Magick;" part is something I was just trying recently
> 
> however when I try to start the server it gives me this error:
> 
> 
> UserTag 'thumb' subroutine failed compilation:
> 
>         Global symbol "$srcImage" requires explicit package name at (eval
> 99) line 12, <GLOBAL> chunk 426.
>  syntax error at (eval 99) line 12, near "@ ;
>        my "

Please pay attention to the error -- it is telling you exactly what is
going wrong. Your routine's syntax is bad.

If you use a reasonable programmer's editor (I use VIM), then you
can do in-editor syntax checks.

For VIM, I just use the visual highlighting feature and do

	!perl -Mstrict -wc

to pipe it through "perl -Mstrict -wc". That will check the syntax,
enforcing strict as we are wont to do.

Once I fix your syntax error by placing an underscore after
the @ sign, I do that and get:

    Useless use of reference constructor in void context at - line 18.
    - syntax OK

Note also that your eval is a good idea, but the "use Image::Magick"
below it ruins the concept. You don't need the "use".

-- 
Mike Heins
Perusion -- Expert Interchange Consulting    http://www.perusion.com/
phone +1.513.523.7621      <mike@perusion.com>

Being against torture ought to be sort of a bipartisan thing.
-- Karl Lehenbauer