Version: 4.2.1

3 Special Subforms

    3.1 Subforms and Keywords

    3.2 Subforms with Expansion Contexts

    3.3 Subforms with Internal Definition Contexts

    3.4 Inspecting Expanded Code

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.