\
\ co.fs Coroutines by continuations.
\
\ * Circular Queue. Capacity is power of 2.
\
VARIABLE HEAD VARIABLE TAIL
128 CELLS CONSTANT CQ#
\ * align by queue capacity
HERE DUP
CQ# 1- INVERT AND CQ# +
SWAP - ALLOT
\
HERE CQ# ALLOT CONSTANT START
\
: ADJUST ( -- ) [ CQ# 1- ]L AND START + ;
: PUT ( n-- ) TAIL @ TUCK ! CELL+ ADJUST TAIL ! ;
: TAKE ( --n ) HEAD @ DUP @ SWAP CELL+ ADJUST HEAD ! ;
: 0CQ ( -- ) START DUP HEAD ! TAIL ! ; 0CQ
: NOEMPTY? ( --f ) HEAD @ TAIL @ <> ;
: ;CO ( -- ) TAKE >R ;
\
\ * COROUTINES LEXEME
\
: CO: ( -- ) R> PUT ; \ Register continuation as coroutine. Exit.
: CO ( -- ) R> PUT TAKE >R ; \ Co-route.
: GO ( -- ) BEGIN NOEMPTY? WHILE ;CO REPEAT ; \ :-)
\
\ * CHANNELS LEXEME
\
: CHAN? ( a--f ) 2@ XOR ;