syntax-case

[syntax] syntax-case exp (literal ...) clause ...

ChezScheme: lower layer of hygienic macro expander.

The following syntax and procedures are also used to implement lower layer of hygienic macro: syntax, identifier?, identifier-syntax, bound-identifier=?, free-identifier=?, literal-identifier=?, with-syntax, syntax-object->datum, datum->syntax-object.

Chicken also has it in syntax-case unit.