Instantiable bodies are sequences of forms defined in a lexical context
and usable in another lexical context with some preliminary processing.
The following syntactic bindings are exported by the library
(vicare language-extensions instantiable-bodies).
Define a new syntax bound to the syntactic identifier ?definer which, when used, expands to the ?body forms. The defined syntax must be used as follows:
(?definer ((?from ?to) ...))
where ?from must be a syntactic identifier and ?to can be any form. Before the expansion: all the occurrences of the syntactic identifiers ?from are replaced by the associated syntactic identifiers ?to.
Here is a simple example:
(define-instantiable-body definer (define (fun) const)) (definer ((fun doit) (const 123))) (doit) ⇒ 123
the use of the syntax
definer expands into:
(define (doit) 123)