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Full Discussion: Perl syntax that I don't understand.
Top Forums Shell Programming and Scripting Perl syntax that I don't understand. Post 302522081 by mrwatkin on Friday 13th of May 2011 09:26:43 AM
Old 05-13-2011
Perl syntax that I don't understand.
I'm just trying to confirm that I understand someone's code correctly.

If someone has code that says:
Code:
$foo ||= mysub();

I'm assuming that it means if $foo is nothing or undef, then assign it some value via mysub(). If I'm wrong on this, please let me know.


Also, what's the difference between this:

Code:
$somescalar = [['one','two'],['three','four']];

and this:

Code:
@myarray = (['one','two'],['three','four']);

I'm assuming they both do the same thing and create a new list of lists in memory. The first one is a reference to the list of lists while the other is the actual list(array) of lists itself. If I'm wrong here, please let me know. I'm probably only 40-70 hours into perl. I've coded in other languages before, but syntax is usually the big hurdle for me.
Last edited by mrwatkin; 05-13-2011 at 10:32 AM..
 

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LEARN ABOUT SUSE

gtk2::pagesetup

Gtk2::PageSetup(3)					User Contributed Perl Documentation					Gtk2::PageSetup(3)

NAME

       Gtk2::PageSetup

HIERARCHY

	 Glib::Object
	 +----Gtk2::PageSetup

METHODS

   pagesetup = Gtk2::PageSetup->new
   pagesetup = Gtk2::PageSetup->new_from_file ($file_name)
       o   $file_name (localized file name)

       May croak with a Glib::Error in $@ on failure.

       Since: gtk+ 2.12

   pagesetup = Gtk2::PageSetup->new_from_key_file ($key_file, $group_name)
       o   $key_file (Glib::KeyFile)

       o   $group_name (string or undef)

       May croak with a Glib::Error in $@ on failure.

       Since: gtk+ 2.12

   double = $setup->get_bottom_margin ($unit)
       o   $unit (Gtk2::Unit)

   $setup->set_bottom_margin ($margin, $unit)
       o   $margin (double)

       o   $unit (Gtk2::Unit)

   double = $setup->get_left_margin ($unit)
       o   $unit (Gtk2::Unit)

   $setup->set_left_margin ($margin, $unit)
       o   $margin (double)

       o   $unit (Gtk2::Unit)

   $setup->load_file ($file_name)
       o   $file_name (string)

       May croak with a Glib::Error in $@ on failure.

       Since: gtk+ 2.14

   $setup->load_key_file ($key_file, $group_name)
       o   $key_file (Glib::KeyFile)

       o   $group_name (string or undef)

       May croak with a Glib::Error in $@ on failure.

       Since: gtk+ 2.14

   pageorientation = $setup->get_orientation
   $setup->set_orientation ($orientation)
       o   $orientation (Gtk2::PageOrientation)

   double = $setup->get_page_height ($unit)
       o   $unit (Gtk2::Unit)

   double = $setup->get_page_width ($unit)
       o   $unit (Gtk2::Unit)

   double = $setup->get_paper_height ($unit)
       o   $unit (Gtk2::Unit)

   $setup->set_paper_size_and_default_margins ($size)
       o   $size (Gtk2::PaperSize)

   papersize = $setup->get_paper_size
   $setup->set_paper_size ($size)
       o   $size (Gtk2::PaperSize)

   double = $setup->get_paper_width ($unit)
       o   $unit (Gtk2::Unit)

   double = $setup->get_right_margin ($unit)
       o   $unit (Gtk2::Unit)

   $setup->set_right_margin ($margin, $unit)
       o   $margin (double)

       o   $unit (Gtk2::Unit)

   $setup->to_file ($file_name)
       o   $file_name (localized file name)

       May croak with a Glib::Error in $@ on failure.

       Since: gtk+ 2.12

   $setup->to_key_file ($key_file, $group_name)
       o   $key_file (Glib::KeyFile)

       o   $group_name (string or undef)

       Since: gtk+ 2.12

   double = $setup->get_top_margin ($unit)
       o   $unit (Gtk2::Unit)

   $setup->set_top_margin ($margin, $unit)
       o   $margin (double)

       o   $unit (Gtk2::Unit)

ENUMS AND FLAGS

   enum Gtk2::PageOrientation
       o   'portrait' / 'GTK_PAGE_ORIENTATION_PORTRAIT'

       o   'landscape' / 'GTK_PAGE_ORIENTATION_LANDSCAPE'

       o   'reverse-portrait' / 'GTK_PAGE_ORIENTATION_REVERSE_PORTRAIT'

       o   'reverse-landscape' / 'GTK_PAGE_ORIENTATION_REVERSE_LANDSCAPE'

   enum Gtk2::Unit
       o   'pixel' / 'GTK_UNIT_PIXEL'

       o   'points' / 'GTK_UNIT_POINTS'

       o   'inch' / 'GTK_UNIT_INCH'

       o   'mm' / 'GTK_UNIT_MM'

SEE ALSO

       Gtk2, Glib::Object

COPYRIGHT

       Copyright (C) 2003-2008 by the gtk2-perl team.

       This software is licensed under the LGPL.  See Gtk2 for a full notice.

perl v5.12.1							    2010-07-05							Gtk2::PageSetup(3)
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