wrap-callback-quot ( params quot -- quot' )

Vocabulary

stack-checker.alien

Inputs

params	an alien-node-params
quot	a quotation

Outputs

quot'

a quotation

Word description

Wraps the given quotation in protective packaging so that it becomes suitable to be used as an alien callback. That means that the parameters are unpacked from C types to Factor types and, if the callback returns something, the top data stack item is afterwards converted to a C compatible value.

Examples

Here a callback that returns the length of a c-string is wrapped:

USING: alien.c-types prettyprint stack-checker.alien ; T{ alien-node-params { return int } { parameters { c-string } } } [ length ] wrap-callback-quot . [ [ { object } declare [ ] dip utf8 alien>string length >fixnum ] [ dup current-callback eq? [ drop ] [ wait-for-callback ] if ] do-callback
]

Definition

IN: stack-checker.alien

GENERIC: wrap-callback-quot ( params quot -- quot' )

Methods

USING: alien.private kernel namespaces quotations sequences
stack-checker.alien ;

M: callable wrap-callback-quot
    swap [ callback-parameter-quot ] [ callback-return-quot ] bi
    surround wait-for-callback-hook get [ do-callback ] 2curry
    >quotation ;