>And the language is the actual language I'm working with, not something that needs its own parser to give me less functionality in the spirit of mollyguarding on behalf of people who make mistakes of classes I categorically refuse to allow in my systems.

Ok. But to be fair, Twig's parser is extensible, whereas PHP's isn't. And it lets you use array shorthand in PHP versions that don't support it (which is not as much of a problem as it used to be, but to me, more than worth never having to type "Array()" again.)

Have you tried the XHP functionality in Hack? It treats XML as objects and understands it in context (which is something PHP should do natively, but can't.) It seems to solve many of the footgun problems that PHP template languages do, within native code.