Thank you very much for all your answers! I come from a JavaScript background, and in JavaScript when you make a function call, a copy of each variable is passed to the function, but if the variable is an array, then only a reference is passed. So, writing to that array will change the original array as well. It's confusing when you combine it with perl. Lol But I am trying to sort it out. 
// The only way to work with arrays in JavaScript:

myArray = [0, 1, 2, 3, 4];

ChangeArrayJS(myArray);

function ChangeArrayJS(ARRAY)
{
  ARRAY[2] = 'JS';     // changes myArray

  var COPY_OF_ARRAY = ARRAY;
  COPY_OF_ARRAY[2] = 'this will be lost';
}

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In reply to Re^2: Changing an array from a sub by harangzsolt33
in thread Changing an array from a sub by harangzsolt33

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