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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 DEBIAN

locale::language

Locale::Language(3perl) 				 Perl Programmers Reference Guide				   Locale::Language(3perl)

NAME

       Locale::Language - standard codes for language identification

SYNOPSIS

	  use Locale::Language;

	  $lang = code2language('en');	      # $lang gets 'English'
	  $code = language2code('French');    # $code gets 'fr'

	  @codes   = all_language_codes();
	  @names   = all_language_names();

DESCRIPTION

       The "Locale::Language" module provides access to standard codes used for identifying languages, such as those as defined in ISO 639.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 639 two-
       letter codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying languages. The ones currently supported are:

       alpha-2
	   This is the set of two-letter (lowercase) codes from ISO 639, such as 'he' for Hebrew.

	   This code set is identified with the symbol "LOCALE_LANG_ALPHA_2".

	   This is the default code set.

       alpha-3
	   This is the set of three-letter (lowercase) bibliographic codes from ISO 639, such as 'heb' for Hebrew.

	   This code set is identified with the symbol "LOCALE_LANG_ALPHA_3".

       term
	   This is the set of three-letter (lowercase) terminologic codes from ISO 639.

	   This code set is identified with the symbol "LOCALE_LANG_TERM".

ROUTINES

       code2language ( CODE [,CODESET] )
       language2code ( NAME [,CODESET] )
       language_code2code ( CODE ,CODESET ,CODESET2 )
       all_language_codes ( [CODESET] )
       all_language_names ( [CODESET] )
       Locale::Language::rename_language  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Language::add_language  ( CODE ,NAME [,CODESET] )
       Locale::Language::delete_language  ( CODE [,CODESET] )
       Locale::Language::add_language_alias  ( NAME ,NEW_NAME )
       Locale::Language::delete_language_alias	( NAME )
       Locale::Language::rename_language_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Language::add_language_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Language::delete_language_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes man page.

SEE ALSO

       Locale::Codes
       Locale::Constants
       http://www.loc.gov/standards/iso639-2/
	   Source of the ISO 639 codes.

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 1997-2001 Canon Research Centre Europe (CRE).
	  Copyright (c) 2001-2010 Neil Bowers
	  Copyright (c) 2010-2011 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.14.2							    2011-09-26						   Locale::Language(3perl)
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