The minimum set of `+!()[]` chars are proven to be TC [0]
So good luck trying to define a non-TC js-subset that allows to use these chars.
So good luck trying to define a non-TC js-subset that allows to use these chars.
[ ] subscript operator except when the subscript is a numeric literal or string literal or an expression that must produce a number value. So expressions like a[i] are disallowed because we cannot statically determine that i is not one of the dangerous property names. But a[+i] is allowed, because +i will always produce a number.