Formal comment #114 (enhancement) identifier macros with syntax-rules Reported by: David Van Horn Component: macros Version: 5.91 Summary It should be possible to define identifier macros using only the base library. Description The (r6rs syntax-case) library allows for identifier macros to be defined, however their specification is orthogonal to both non-hygienic macro expansion and the ability to evaluate arbitrary Scheme code at expansion time, thus it should be possible to define identifier macros in terms of syntax-rules. This implies extending the production to include an underscore, having syntax-rules forms evaluate to transformers, and moving make-variable-transformer to the base library. RESPONSE: The editors agree that adding the ability to define variable transformers to the base library is a good idea but have decided to solve the problem by making identifier-syntax part of the base library rather than by extending syntax-rules and adding make-variable-transformer.