syntax_data: {"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"[Some(unit),"}]}
source_snippet:             [Some(unit), None, None, None, None, None, None, None],
context_before:         arg.cast_to(CastTarget::prefixed(
context_after:             Uniform::new(unit, Size::ZERO),