What did you try that didn't work?

Here are some examples that might help:

# this prints "something" with extra layers of pointless recursion:
print (eval (eval (eval (eval (eval (eval "something")))));

# prints 1024
$it = "ev"."al (".substr("devaluation",1,4) . "(2+2)" ."*"x2 . " 3)";
foreach (0..3) { $it = "eval($it) * 2" }

print eval($it);
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