Do you know of any template based macro systems which are more powerful than syntax-rules, but without going to the other extreme of full turing completeness? A

Do you know of any template based macro systems which are more powerful than syntax-rules, but without going to the other extreme of full turing completeness? As I understand it, syntax-rules doesn't even let you concatenate strings to create new identifiers - everything in the output must come verbatim from the input or the template.