Consult perlfunc, which contains this excerpt from eval:

With an "eval", you should be especially careful to remember what's being looked at when:

eval $x;            # CASE 1
eval "$x";          # CASE 2

eval '$x';          # CASE 3
eval { $x };        # CASE 4

eval "\$$x++";      # CASE 5
$$x++;              # CASE 6

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Cases 1 and 2 above behave identically: they run the code contained in the variable $x. (Although case 2 has misleading double quotes making the reader wonder what else might be happening (nothing is).) Cases 3 and 4 likewise behave in the same way: they run the code '$x', which does nothing but return the value of $x. (Case 4 is preferred for purely visual reasons, but it also has the advantage of compiling at compile-time instead of at run-time.) Case 5 is a place where normally you would like to use double quotes, except that in this particular situation, you can just use symbolic references instead, as in case 6.

In reply to Re: Confusion with eval by eibwen
in thread I solved my Problem! (Confusion with eval) by DrWhy

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