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Full Discussion: #define in perl
Top Forums UNIX for Dummies Questions & Answers #define in perl Post 302143376 by cbkihong on Thursday 1st of November 2007 03:33:59 AM
Old 11-01-2007
Quote:
Originally Posted by srinivasan_85
Hi,
Thanks for your quick suggestion. I grazed over the 'constant' pragma.
From the given link,
Code:
 it's probably not correct to put a constant declaration inside of a conditional statement

My main aim is to use the constant in a 'if' condition.
To elaborate, my scenario is:
Code:
if(defined($input_file)) {
  open(FH,"<$input_file);
  #define INPUT "FH";
} else {
  #define INPUT "STDIN";
}
while ($line = <INPUT>) {
...
}

Then that is not strictly a "constant".

Why do you have to do it like that? You can take a reference of a filehandle and then use it with the slurp ( <> ).

Code:
if(defined($input_file)) {
  open(FH,"<$input_file);
  $input = \*FH;
} else {
  $input = \*STDIN;
}
while ($line = <$input>) {
...
}

 

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LEARN ABOUT OSX

locale::codes::langvar

Locale::Codes::LangVar(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangVar(3pm)

NAME

       Locale::Codes::LangVar - standard codes for language variation identification

SYNOPSIS

	  use Locale::Codes::LangVar;

	  $lvar = code2langvar('acm');		       # $lvar gets 'Mesopotamian Arabic'
	  $code = langvar2code('Mesopotamian Arabic'); # $code gets 'acm'

	  @codes   = all_langvar_codes();
	  @names   = all_langvar_names();

DESCRIPTION

       The "Locale::Codes::LangVar" module provides access to standard codes used for identifying language variations, such as those as defined in
       the IANA language registry.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default IANA language
       registry codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying language variations. A code set may be specified using either a name, or
       a constant that is automatically exported by this module.

       For example, the two are equivalent:

	  $lvar = code2langvar('en','alpha-2');
	  $lvar = code2langvar('en',LOCALE_CODE_ALPHA_2);

       The codesets currently supported are:

       alpha
	   This is the set of alphanumeric codes from the IANA language registry, such as 'arevela' for Eastern Armenian.

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

	   This is the default code set.

ROUTINES

       code2langvar ( CODE [,CODESET] )
       langvar2code ( NAME [,CODESET] )
       langvar_code2code ( CODE ,CODESET ,CODESET2 )
       all_langvar_codes ( [CODESET] )
       all_langvar_names ( [CODESET] )
       Locale::Codes::LangVar::rename_langvar  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::LangVar::add_langvar  ( CODE ,NAME [,CODESET] )
       Locale::Codes::LangVar::delete_langvar  ( CODE [,CODESET] )
       Locale::Codes::LangVar::add_langvar_alias  ( NAME ,NEW_NAME )
       Locale::Codes::LangVar::delete_langvar_alias  ( NAME )
       Locale::Codes::LangVar::rename_langvar_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangVar::add_langvar_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangVar::delete_langvar_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.iana.org/assignments/language-subtag-registry
	   The IANA language subtag registry.

AUTHOR

       See Locale::Codes for full author history.

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

COPYRIGHT

	  Copyright (c) 2011-2012 Sullivan Beck

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

perl v5.16.2							    2012-10-11					       Locale::Codes::LangVar(3pm)
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