factor/extra/pair-methods/pair-methods.factor

59 lines
1.7 KiB
Factor

! Copyright (C) 2009 Joe Groff.
! See http://factorcode.org/license.txt for BSD license.
USING: arrays assocs classes classes.tuple.private combinators
effects.parser generic.parser kernel math math.order parser
quotations sequences sorting words ;
IN: pair-methods
ERROR: no-pair-method a b generic ;
: ?swap ( a b ? -- a/b b/a )
[ swap ] when ;
: method-sort-key ( pair -- key )
first2 [ tuple-layout third ] bi@ + ;
: pair-match-condition ( pair -- quot )
first2 [ [ instance? ] swap prefix ] bi@ [ ] 2sequence
[ 2dup ] [ bi* and ] surround ;
: pair-method-cond ( pair quot -- array )
[ pair-match-condition ] [ ] bi* 2array ;
: sorted-pair-methods ( word -- alist )
"pair-generic-methods" word-prop >alist
[ first method-sort-key ] inv-sort-with ;
: pair-generic-definition ( word -- def )
[ sorted-pair-methods [ first2 pair-method-cond ] map ]
[ [ no-pair-method ] curry suffix ] bi 1quotation
[ 2dup [ class-of ] compare +gt+ eq? ?swap ] [ cond ] surround ;
: make-pair-generic ( word -- )
dup pair-generic-definition define ;
: define-pair-generic ( word effect -- )
[ set-stack-effect ]
[ drop H{ } clone "pair-generic-methods" set-word-prop ]
[ drop make-pair-generic ] 2tri ;
: (PAIR-GENERIC:) ( -- )
scan-new-generic scan-effect define-pair-generic ;
SYNTAX: PAIR-GENERIC: (PAIR-GENERIC:) ;
: define-pair-method ( a b pair-generic definition -- )
[ 2array ] 2dip swap
[ "pair-generic-methods" word-prop swapd set-at ]
[ make-pair-generic ] bi ;
: ?prefix-swap ( quot ? -- quot' )
[ \ swap prefix ] when ;
: (PAIR-M:) ( -- )
scan-word scan-word 2dup <=> +gt+ eq? [
?swap scan-word parse-definition
] keep ?prefix-swap define-pair-method ;
SYNTAX: PAIR-M: (PAIR-M:) ;