Re: Dynamically Building Variable Names

I agree with Fletch that you probably don't want it.

I can see some vague utility if you want to access global variables. In this case, you can use a plain hash to get a quick hack that works even with strict and warnings turned on:

   #!/usr/bin/perl
   use strict;    # Use good practices
   use warnings;

   my %globals = (barbaz => "something here");
   foo("bar", "baz");

   sub foo {
      my $name = join('', @_);     # Build varname
      print $globals{$name}, "\n"; # use it at will....
   }
[download]

If you want to go the dark-side way (but remember that it's difficult to get back!), you have to indirect the variable name you're building:

   #!/usr/bin/perl
   $barbaz = "something here";
   foo("bar", "baz");

   sub foo {
      $name = join('', @_);  # Build varname
      print $$name, "\n";    # use it AT YOUR RISK!
   }
[download]

But, at the risk of repeating myself and Fletch, you don't want to do that.

Flavio (perl -e 'print(scalar(reverse("\nti.xittelop\@oivalf")))')

Don't fool yourself.

Comment on Re: Dynamically Building Variable Names Select or Download Code

Replies are listed 'Best First'.
Re^2: Dynamically Building Variable Names by dragonchild (Archbishop) on Apr 22, 2005 at 17:33 UTC
Just to hammer the point home even more - your second example is identical to `#!/usr/bin/perl $barbaz = "something here"; foo("bar", "baz"); sub foo { $name = join('', @_); # Build varname print $main::{$name}, "\n"; }` [download] In other words, you're using a hash - the package's symbol table. However, if you don't want to clobber something, use your own hash. My wife's blog	[reply] [d/l]