- (warning-guard GETTER-NAME TYPENAME [BODY...])syntax
Constructs a variable or parameter guard procedure that generates a warning and returns the current value when the type predicate fails, otherwise the submitted value is returned.
TYPENAME is an identifier and TYPENAME? is a (procedure (*) boolean).
GETTER-NAME is an identifier and the name of a procedure _ *.
BODY is zero or more expressions that are performed after a successful typecheck. Note that since the guard is invoked by a variable or parameter during initialization, so will be the body code.
(use variable-item) (warning-guard some-var integer)