define-foreign-pointer Macro

Summary

Defines a new FLI pointer type.

Package

fli

Signature

define-foreign-pointer name-and-options points-to-type &rest slots => type-name

name-and-options ::= type-name | (type-name (option*))

option ::= (option-name option-value)

Arguments

Values

Description

The macro define-foreign-pointer defines two things:

• An FLI pointer type type-name, which is a pointer to points-to-type.
• A Lisp type specifier type-name that is a foreign pointer.

The option :allow-null takes an option-value of either t or nil, defaulting to nil. It controls whether the type type-name accepts nil.

The other allowed values for option-name are the defstruct options :conc-name, :constructor, :predicate, :print-object, :print-function. In each case the symbol supplied as option-value provides the corresponding option for type-name.

slots is a list of defstruct slot-descriptions which become slots in type-name.

When LispWorks makes a foreign pointer of type type-name, then an object of Lisp type type-name is made instead of a foreign pointer object. This is useful if you want to associate extra Lisp data with the foreign pointer object, using slots.

See also

3.1.1 Creating pointers