PerlInfo

Tricky perl syntax

If you are new to perl, mh can be intimidating, there is a nice perl faq written by Robert ? at : http://www.sthomas.net/roberts-perl-tutorial.htm

After becoming familiar, the next hurdle are the perl object methods.

e.g. set $couch_lamp ON; $couch_lamp->set(ON);

both do exactly the same thing.

Most of the MH code is written in the style of perl that minimizes the extra punctuation. I thought maybe this would help. In perl:

functionname($arg1, $arg2, $arg3);

can usually be replaced by

functionname $arg1, $arg2, $arg3;

and

$object->method($arg1, $arg2, $arg3);

can usually be replaced by

method $object $arg1, $arg2, $arg3;

I suppose people that are very familiar with perl like to write it without the parens and "->" but for someone trying to figure out perl syntax it is very confusing. Then you can add things that look like new keywords but aren't:

use constant OFF => 'off'

All this means that you can write something neat looking:

set $light OFF

But for a new perl programmer, this is easier to understand:

$light->set('off');

In my opinion, if you try to use the "set $light OFF" syntax and you don't understand these shortcuts then your programming will continuously be by trial and error. I certainly don't have all the subtleties of the perl order of operations memorized so I don't write it like that.