factor/core/classes/union/union.factor

97 lines
2.7 KiB
Factor

! Copyright (C) 2004, 2011 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors assocs classes classes.algebra
classes.algebra.private classes.builtin classes.private
combinators definitions kernel kernel.private math math.private
quotations sequences sets words ;
IN: classes.union
PREDICATE: union-class < class
"metaclass" word-prop union-class eq? ;
<PRIVATE
GENERIC: union-of-builtins? ( class -- ? )
M: builtin-class union-of-builtins? drop t ;
M: union-class union-of-builtins?
class-members [ union-of-builtins? ] all? ;
M: class union-of-builtins?
drop f ;
: fast-union-mask ( class -- n )
[ 0 ] dip flatten-class
[ drop class>type 2^ bitor ] assoc-each ;
: empty-union-predicate-quot ( class -- quot )
drop [ drop f ] ;
: fast-union-predicate-quot ( class -- quot )
fast-union-mask 1quotation
[ tag 1 swap fixnum-shift-fast ]
[ fixnum-bitand 0 eq? not ]
surround ;
: slow-union-predicate-quot ( class -- quot )
class-members [ predicate-def ] map unclip swap
[ [ dup ] prepend [ drop t ] ] { } map>assoc alist>quot ;
: union-predicate-quot ( class -- quot )
{
{ [ dup class-members empty? ] [ empty-union-predicate-quot ] }
{ [ dup union-of-builtins? ] [ fast-union-predicate-quot ] }
[ slow-union-predicate-quot ]
} cond ;
: define-union-predicate ( class -- )
dup union-predicate-quot define-predicate ;
M: union-class update-class define-union-predicate ;
: (define-union-class) ( class members -- )
f swap f union-class make-class-props (define-class) ;
ERROR: cannot-reference-self class members ;
GENERIC: classes-contained-by ( obj -- members )
M: union-class classes-contained-by ( union -- members )
"members" word-prop [ f ] when-empty ;
M: object classes-contained-by
"members" word-prop [ f ] when-empty ;
: check-self-reference ( class members -- class members )
2dup [
dup dup [ classes-contained-by ] map concat sift append
2dup set= [ 2drop f ] [ nip ] if
] follow concat
member-eq? [ cannot-reference-self ] when ;
PRIVATE>
: define-union-class ( class members -- )
[ check-self-reference (define-union-class) ]
[ drop changed-conditionally ]
[ drop update-classes ]
2tri ;
M: union-class rank-class drop 7 ;
M: union-class instance?
"members" word-prop [ instance? ] with any? ;
M: anonymous-union instance?
members>> [ instance? ] with any? ;
M: anonymous-union class-name
members>> [ class-name ] map " " join ;
M: union-class normalize-class
class-members <anonymous-union> normalize-class ;
M: union-class (flatten-class)
class-members <anonymous-union> (flatten-class) ;