3 Special Subforms

Special subforms are syntactic forms that are used as part of the syntax of other syntactic forms. Unlike expressions and definitions, they have no intrinsic interpretation. A special subform’s interpretation is given by the macro or primitive form whose syntax includes it.

The else keyword (within a cond expression) and public method declarations (with a class expression) are examples of special subforms.

Special subforms are different from Context-Sensitive Macros, which are expression or definition forms, but whose behavior depend on the context in which they are used.