This problem is not quite as simple as it seems. There are a number of cpan ways to read a parm file. Lets bypass that for now and focus on the replacement. The replace pairs are already in hashs that are part of an ORDERED array here. 

use strict; use warnings; 

my @reps; 
push @reps,{from=>'ZZZ',to=>'456AAA456'}; 
push @reps,{from=>'AAA',to=>'AAA123'}; 
push @reps,{from=>'BBB',to=>'XYZ999'}; 
push @reps,{from=>'DEF',to=>'ANYOTHER'}; 

while (my $line=<DATA>) { 
  chomp $line; 
  for my $rep (@reps){ 
    my $from=$rep->{from}; 
    my $to  =$rep->{to}; 
    $line=~s/\Q$from\E/$to/g; 
    } # rep 
  print $line."\n"; 
  } # line 

__DATA__
AAAA more stuff 
stuff BBB again 
DEF stuff 
|ZZZZ| not as simple as it seems

[download]
Result 
AAA123A more stuff
stuff XYZ999 again
ANYOTHER stuff
|456AAA123456Z| not as simple as it seems

[download]
As you can see, if a "to" contains a "from" the order of execution is important. There is a lot that could be improved here, pre-compiling the regexp parts for instance, but this is a simple demo of how it can be done and one of the pitfalls.

In reply to Re: string replacement by huck
in thread string replacement by colox

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