Is there perhaps a more elegant way to do this?

If you you input and output redirection, you can let the shell do the file handling for you.

while (<>) {    
   s/$searchPattern1/$repalcePattern1/g;
   s/$searchPattern2/$replacePattern2/g;
   s/$searchPattern3/$replacePattern3/g;
   print;
}
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but that doesn't seem to be working

while (<>) {
   if (s/$searchPattern1/$repalcePattern1/g) {
      warn("$searchPattern1 replaced with $replacePattern1\n");
   }

   elsif (s/$searchPattern2/$repalcePattern2/g) {
      warn("$searchPattern2 replaced with $replacePattern2\n");
   }

   elsif (s/$searchPattern3/$repalcePattern3/g) {
      warn("$searchPattern3 replaced with $replacePattern3\n");
   }

   else {
      warn("Search Patterns not found\n");
   }

   print;
}
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Note that you used to search for all three patterns. Now you stop after one succeeds in replacing something.

is there a way to remove all the spaces at the end of a line and add a new line character?

s/\s*\z/\n/;
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