OK, here is something I have never really been able to understand very well. Say I am running through a file, and I use a regex to match a certain condition: 
while (<FILE>) {
   if (/.../) { 
     ... 
   }
}

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(The ... are not intended to be perl operators, they just mean 'something else goes here').
Easy enough. Now say that in the regex in the if(), we use parens to pull two strings, which are then assigned to $1 and $2, obviously. Now lets also say that as we run through this file, we use another regex to find a different pattern, which then matches another string ($1 again), which is then assigned to a global varible called, oh, '$stuff'. So here is the whole situation, pretty much: 
my $stuff;

while (<FILE>) {
   if (/(...)(...)/) {
      # we have $1 and $2 in here, both some string
   } elsif (/(...)/) {
      $stuff = $1;
   }
}

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(Obviously, this is all psuedo-code because my actual code is very messy and would not suffice for this discussion, but you get the idea.) Now here is where I get stuck. In the if() clause above (where $1 and $2 are assigned) I want to assign a hash value on the fly. Here is what I want to do (assume that anytime we are in the if(), $stuff has a value that was already assigned in the elsif() - in my code, it has to happen this way): 
eval "\$$stuff{$1} = $2";

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but as you can imagine, this does not in fact work. Now, I have never really been good at the whole reference thing and dynamic varible creation and such, so could someone please explain to me how I would do what I have illustrated above? I have a feeling that it is in fact a rather simple solution, but I continualy find myself up against a wall in this area!

Thanks so much,
R.Joseph

In reply to Creating on-the-fly hashes? by r.joseph

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