Error with my perl script when i generate a script to cvs checkout

NikhilRangaraju has asked for the wisdom of the Perl Monks concerning the following question:

Here is the code that i wrote...

#!/usr/bin/perl

use File::Basename;

#---------------------------------------------------------------------
+---------

my $Product   = 'LegalCraft';

my $Options   = '';

my %Win32     = ( 'checkout' => Checkout,
                  'co'       => Checkout,
                  'clean'    => Clean,
                  'build'    => Build     );

my %Linux     = ( 'checkout' => Checkout,
                  'co'       => Checkout,
                  'clean'    => Clean,
                  'build'    => Build     );

my %Platforms = ( 'win32' => \%Win32,
                  'linux' => \%Linux );

Dispatch();

#---------------------------------------------------------------------
+---------

sub Dispatch
{
   if ( exists( $Platforms{ lc( $ENV{PLATFORM} ) } ) )
   {
      print "\nProduct $Product - Platform $ENV{PLATFORM} supported!\n
+";
   }
   else
   {
      print "\nProduct $Product - Not implemented ".
            "for platform $ENV{PLATFORM}\n";
      return;
   }

   my $FnTable = $Platforms{ lc( $ENV{PLATFORM} ) };
   for ( @ARGV )
   {
      if ( exists( $FnTable->{ lc( $_ ) } ) )
      {
         print "\nProduct $Product - Platform $ENV{PLATFORM} - Functio
+n $_\n";
         $FnTable->{ lc( $_ ) }();
         $Options = '';
      }
      else
      {
         $Options .= " $_";
      }
   }

  print "\n";
}


sub ChProdDir
{
   $_ = __FILE__;
   tr/\\/\//;
   chdir dirname $_;
   chdir '..';
}



BEGIN
{
   ChProdDir();
}


sub Checkout
{
   system "./cvs $Options checkout";

   chdir '..';
   system "cvs co $ENV{IMCOOPT} $Options viewer";

   ChProdDir();
}
[download]

When i compiled it, "Product Legalcraft is not implemented for Platform " is shown as error and i couldnot understand what is the logic behind Diapatch() function.

Comment on Error with my perl script when i generate a script to cvs checkout Download Code

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Re: Error with my perl script when i generate a script to cvs checkout by Corion (Patriarch) on Feb 20, 2006 at 12:37 UTC
You seem to be changing a program without understanding it or understanding what it is supposed to do. This is a problematic and dangerous practice. The error message is output by the script itself, in the `sub Dispatch`, whenever it does not find a supported platform. If you had run your program with warnings enabled, like I suggested when you last posted, Perl would have told you that you used a variable which was not initialized. In this case, it is `$ENV{PLATFORM}`, most likely, because you did not set the `PLATFORM` environment variable. You could change `Dispatch` like this to make the program give you a more explicit error message: sub Dispatch { if ( exists( $Platforms{ lc( $ENV{PLATFORM} ) } ) ) { print "\nProduct $Product - Platform $ENV{PLATFORM} supported!\n +"; } elsif (defined $ENV{PLATFORM}) { print "\nProduct $Product - Not implemented ". "for platform $ENV{PLATFORM}\n"; return; } else { print "\nThe environment variable PLATFORM was not set.\n"; return; } my $FnTable = $Platforms{ lc( $ENV{PLATFORM} ) }; for ( @ARGV ) { if ( exists( $FnTable->{ lc( $_ ) } ) ) { print "\nProduct $Product - Platform $ENV{PLATFORM} - Functio +n $_\n"; $FnTable->{ lc( $_ ) }(); $Options = ''; } else { $Options .= " $_"; } } print "\n"; } [download] The code also seems to be somewhat problematic or weird, because it calls the functions `Checkout`, `Clean` and `Build` when building the hashes; at least assuming you left out the definitions of these subroutines. Otherwise, if these are to be strings, you should put them into quotes to clearly mark them as strings.	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re: Error with my perl script when i generate a script to cvs checkout
by Corion (Patriarch) on Feb 20, 2006 at 12:37 UTC

You seem to be changing a program without understanding it or understanding what it is supposed to do. This is a problematic and dangerous practice.

The error message is output by the script itself, in the sub Dispatch, whenever it does not find a supported platform. If you had run your program with warnings enabled, like I suggested when you last posted, Perl would have told you that you used a variable which was not initialized. In this case, it is $ENV{PLATFORM}, most likely, because you did not set the PLATFORM environment variable.

You could change Dispatch like this to make the program give you a more explicit error message:

sub Dispatch
{
   if ( exists( $Platforms{ lc( $ENV{PLATFORM} ) } ) )
   {
      print "\nProduct $Product - Platform $ENV{PLATFORM} supported!\n
+";
   }
   elsif (defined $ENV{PLATFORM})
   {
      print "\nProduct $Product - Not implemented ".
            "for platform $ENV{PLATFORM}\n";
      return;
   } else {
      print "\nThe environment variable PLATFORM was not set.\n";
      return;
   }

   my $FnTable = $Platforms{ lc( $ENV{PLATFORM} ) };
   for ( @ARGV )
   {
      if ( exists( $FnTable->{ lc( $_ ) } ) )
      {
         print "\nProduct $Product - Platform $ENV{PLATFORM} - Functio
+n $_\n";
         $FnTable->{ lc( $_ ) }();
         $Options = '';
      }
      else
      {
         $Options .= " $_";
      }
   }

  print "\n";
}
[download]

The code also seems to be somewhat problematic or weird, because it calls the functions Checkout, Clean and Build when building the hashes; at least assuming you left out the definitions of these subroutines. Otherwise, if these are to be strings, you should put them into quotes to clearly mark them as strings.

[reply]
[d/l]
[select]