defer_fs

\ defer_fs

\ This file is part of Sfera, a library for SuperForth
\ http://programandala.net/en.program.sfera.html

\ Author: Marcos Cruz (programandala.net), 2016

\ ==============================================================
\ License

\ You may do whatever you want with this work, so long as you
\ retain the copyright/authorship/acknowledgment/credit
\ notice(s) and this license in all redistributed copies and
\ derived works.  There is no warranty.

\ ==============================================================
\ Description

\ This file defines standard Forth's `defer`, `defer!` and
\ `defer@`. 
\ 
\ Words created by `defer` are compatible with Superforth
\ `assign` and `to-do`, while `defer!` and `defer@` are
\ compatible with words created by SuperForth `exvec:`.

\ ==============================================================
\ History

\ 2016-01-25: Adapted from Afera (http://en.program.afera.html).
\
\ 2016-02-08: Removed `end-of-file`.
\
\ 2016-02-11: Simplified `defer` with headerless error word.
\ Added description.

\ ==============================================================

: defer  ( "name" -- )
  create  h# 954C compile,
  does>   ( -- )  ( pfa )  @ execute  ;
  \ Create a deferred word.
  \ Note: $954C is the cfa of the SuperForth headerless word
  \ which issues an "Unassigned execution vector" error.

: defer@  ( cfa1 -- cfa2 )  >body @  ;
  \ _cfa2_ is the code field address the deferred word _cfa1_
  \ is set to execute.

: defer!  ( cfa1 cfa2 -- )  >body !  ;
  \ Set the deferred word _cfa2_ to execute _cfa1_.


\ vim: filetype=superforthsfera