factor/libs/coroutines/coroutines.factor

55 lines
2.3 KiB
Factor

! Copyright (C) 2005 Chris Double.
!
! Redistribution and use in source and binary forms, with or without
! modification, are permitted provided that the following conditions are met:
!
! 1. Redistributions of source code must retain the above copyright notice,
! this list of conditions and the following disclaimer.
!
! 2. Redistributions in binary form must reproduce the above copyright notice,
! this list of conditions and the following disclaimer in the documentation
! and/or other materials provided with the distribution.
!
! THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
! INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
! FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
! DEVELOPERS AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
! SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
! PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
! OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
! WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
! OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
! ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
!
IN: coroutines
USING: kernel generic ;
TUPLE: coroutine resumecc exitcc ;
: cocreate ( quot -- co )
#! Create a new coroutine, which will execute the quotation
#! when resumed. The quotation will have the coroutine
#! on the stack and an initial value (received from coresume)
#! when first resumed. ie. The quotation should have stack
#! effect ( co value -- ).
f f <coroutine> dup rot curry over set-coroutine-resumecc ;
: coresume ( v co -- result )
#! Resume a coroutine with 'v' as the first item on the
#! stack. The result placed on the stack is that of the
#! topmost argument on the stack when coyield is called
#! within the coroutine.
[
over set-coroutine-exitcc
coroutine-resumecc call
] callcc1 rot drop ;
: coyield ( v co -- result )
#! Suspend a coroutine, leaving the value 'v' on the
#! stack when control is passed to the 'coresume' caller.
[
[ continue-with ] curry
over set-coroutine-resumecc
coroutine-exitcc continue-with
] callcc1 rot drop ;