Are you aware that _any_ string interpolation can inject _any_ arbitrary code in a string?

Yes, I know since I said as much in the post to which you replied.

Are you aware that _any_ string interpolation can inject _any_ arbitrary code in a string?

Not true. The one provided by String::Interpolate doesn't.

The native interpolation mechanism does, but we were never talking about that. The OP was proposing a new feature. While I don't see anyone putting in the effort into implementing what is really just another template system, I mentioned that interpolation is not necessarily unsafe, only the current native implementation, and that a safe implementation could be devised.