5.1 Hygienic Macros

R5RS hygienic macro is based on a special pattern language, and guaranteed that no "variable capture" occurs. "Variable catpture" means that if you insert new variable bindings in the expanded form, the new bindings shadows the bindings in the form passed to the macro.

Special Form: define-syntax name transformer-spec

[R5RS]

Special Form: let-syntax ((name transformer-spec) ...) body

Special Form: letrec-syntax ((name transformer-spec) ...) body

[R5RS]

Special Form: syntax-rules literals clause1 clause2 ...

[R5RS]