Re: use constant

[DBSMITH]

                                                                           
             "John W. Krahn"                                               
             <[EMAIL PROTECTED]                                             
             >                                                          To 
                                       Perl Beginners <beginners@perl.org> 
             12/19/2005 08:29                                           cc 
             PM                                                            
                                                                   Subject 
                                       Re: use constant                    
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           







David Gilden wrote:
> Greetings,

Hello,

> I looked for documentation on 'use constant'  but it has eluded it
me.....
>
> my $path =  `pwd`;
> use constant UPLOAD_DIR     => "/home/sites/site123/web/private/_data/";
>
>
> I want to get the Document Root at runtime and concatenate like such...
>
>
> my $path =  `pwd`;

You should probably use the Cwd module to do that.

> use constant UPLOAD_DIR     => "$path/_data/";

use Cwd;

my $path;
BEGIN { $path = cwd }

use constant UPLOAD_DIR => "$path/_data/";



John
--
use Perl;
program
fulfillment

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David,
although there are various ways to do what John stated, the use constant is
not a recomended
pragma according to the Oreilly book "Perl Best Practices."
Rather Readonly is a better method b/c it can be interpolated.

use Readonly;
my $SCALER => 'value';

use Readonly;
my @ARRAY => 'value';

use Readonly;
 my %HASH => 'value';

for versions 5.8 and above

but for versions 5.6 and below

use Readonly::Scaler;
 my $SCALER => 'value';



Derek B. Smith
OhioHealth IT
UNIX / TSM / EDM Teams



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