define-foreign-type

define-foreign-type Macro

Summary

Defines a new FLI type specifier.

Package

fli

Signature

define-foreign-type name-and-options lambda-list &body forms => name

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

option ::= (:foreign-name foreign-name)

Arguments

`lambda-list`⇩	A lambda list which is the argument list of the new FLI type.
`forms`⇩	One or more Lisp forms which provide a definition of the new type.
`name`⇩	A symbol naming the new FLI type.
`foreign-name`⇩	A string specifying the foreign name of the type.

Values

name

The name of the new FLI type.

Description

The macro define-foreign-type defines a new FLI type called name, with optional foreign name foreign-name.

When name is used as a foreign type, forms are evaluated as an implicit progn with the variables in lambda-list bound to the arguments of the foreign type. The value returned by forms is used as the definition of the foreign type. This is similar to how deftype works for Lisp type specifiers.

Notes

foreign-name, specifying the foreign name, is supported only for documentation purposes.

Examples

In the following example an integer array type specifier is defined. Note that the type takes a list as its argument, and uses this to determine the size of the array.

(fli:define-foreign-type :int-array (dimensions)
  `(:c-array :int ,@dimensions))

(setq number-array (fli:allocate-foreign-object
                    :type '(:int-array (2 2))))

In the next example a boolean type, called :bool, with the same size as an integer is defined.

(fli:define-foreign-type :bool () `(:boolean :int))

(fli:size-of :bool)