+! Copyright (C) 2007 Gavin Harrison
+! See http://factorcode.org/license.txt for BSD license.
USING: kernel sequences arrays vectors namespaces math strings
combinators continuations quotations io assocs ;
+++ /dev/null
-
-USING: kernel sequences arrays vectors namespaces math strings
- combinators continuations ;
-
-IN: prolog
-
-SYMBOL: pldb
-SYMBOL: plchoice
-
-: 2dupd ( x y z -- x y x y z ) >r 2dup r> ;
-
-: init-pl ( -- )
- 2 V{ } clone <array> pldb set
- V{ } clone plchoice set ;
-
-: reset-choice ( -- ) V{ } clone plchoice set ;
-: remove-choice ( -- ) plchoice get pop drop ;
-
-: facts ( -- vector ) 0 pldb get nth ;
-: rules ( -- vector ) 1 pldb get nth ;
-: fact ( n -- fact ) dup facts length >= [ drop "No." ] [ facts nth ] if ;
-: rule ( n -- rule ) dup rules length >= [ drop "No." ] [ rules nth ] if ;
-
-: const? ( number/string -- ? )
- dup number? [ nip ]
- [ 0 swap nth dup CHAR: a >= swap CHAR: z <= and ] if* ;
-: var? ( number/string -- ? ) const? not ;
-: check-atom ( string -- ? ) const? ;
-
-: check-fact ( list -- list ? )
- dup t
- [ {
- { [ dup string? ] [ check-atom ] }
- { [ number? ] [ t ] }
- { [ t ] [ f ] }
- } cond and ] reduce ;
-
-: store-fact ( name fact -- ) 2array facts dup length swap set-nth ;
-
-: add-fact ( name fact -- )
- check-fact [ store-fact ] [ drop " not valid" append print ] if ;
-
-: add-choice ( continuation -- )
- dup continuation? [ plchoice get push ] [ drop ] if ;
-
-: last-choice ( -- ) plchoice get pop continue ;
-
-: extract-fact ( fact-entry -- fact ) dup string? [ 1 swap nth ] unless ;
-
-: (lookup-fact) ( name num -- fact )
- dup fact dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup fact [ ] callcc0 add-choice ] when
- dup number? [ 1+ (lookup-fact) ] [ 2nip extract-fact ] if ;
-
-: check-arity ( pattern fact -- pattern fact ? ) 2dup [ length ] 2apply = ;
-
-: (check-elements) ( fact pattern n ? -- ? )
- >r dup zero?
- [ 3drop r> ]
- [ 1 - dup -rot swap dup >r nth dup var?
- [ drop r> swap r> t and (check-elements) ]
- [ >r dupd dup >r swap nth r> r> swap >r = r> swap r> swap r> and swapd
- [ (check-elements) ] [ 3drop f ] if*
- ] if
- ] if ;
-
-: check-elements ( pattern fact -- ? ) swap dup length t (check-elements) ;
-
-: match-pattern ( pattern fact -- ? )
- check-arity [ check-elements ] [ 2drop f ] if ;
-
-: good-result? ( pattern fact -- pattern fact ? )
- 2dup dup "No." = [ 2drop t ] [ match-pattern ] if ;
-
-: lookup-fact ( name pattern -- fact )
- swap 0 (lookup-fact) good-result? [ nip ] [ last-choice ] if ;
-
-: store-rule ( name pattern body -- ) 3array rules dup length swap set-nth ;
-
-: add-rule ( name pattern body -- ) store-rule ;
-
-: (lookup-rule) ( name num -- rule )
- dup rule dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup rule [ ] callcc0 add-choice ] when
- dup number? [ 1+ (lookup-rule) ] [ 2nip ] if ;
-
-! : (init-binds) ( pat-d pat-f binds limit pos -- pat-d pat-f binds limit pos )
-! -rot >r >r dup >r [ swap nth ] curry 2dupd 2apply
-
-! : init-binds ( pat-d pat-f -- pat-d binds )
-
+++ /dev/null
-
-USING: kernel sequences arrays vectors namespaces math strings
- combinators continuations ;
-
-IN: prolog
-
-SYMBOL: pldb
-SYMBOL: plchoice
-
-: 2dupd ( x y z -- x y x y z ) >r 2dup r> ;
-
-: init-pl ( -- )
- 2 V{ } clone <array> pldb set
- V{ } clone plchoice set ;
-
-: reset-choice ( -- ) V{ } clone plchoice set ;
-: remove-choice ( -- ) plchoice get pop drop ;
-
-: facts ( -- vector ) 0 pldb get nth ;
-: rules ( -- vector ) 1 pldb get nth ;
-: fact ( n -- fact ) dup facts length >= [ drop "No." ] [ facts nth ] if ;
-: rule ( n -- rule ) dup rules length >= [ drop "No." ] [ rules nth ] if ;
-
-: var? ( pl-obj -- ? )
- dup string? [ 0 swap nth dup CHAR: A >= swap CHAR: Z <= and ] [ drop f ] if ;
-: const? ( pl-obj -- ? ) var? not ;
-
-: check-atom ( string -- ? ) const? ;
-
-: check-fact ( list -- list ? )
- dup t
- [ {
- { [ dup string? ] [ check-atom ] }
- { [ number? ] [ t ] }
- { [ t ] [ f ] }
- } cond and ] reduce ;
-
-: store-fact ( name fact -- ) 2array facts dup length swap set-nth ;
-
-: add-fact ( name fact -- )
- check-fact [ store-fact ] [ drop " not valid" append print ] if ;
-
-: add-choice ( continuation -- ) plchoice get push ;
-
-: last-choice ( -- ) plchoice get pop continue ;
-
-: extract-fact ( fact-entry -- fact ) dup string? [ 1 swap nth ] unless ;
-
-: (lookup-fact) ( name num -- fact )
- dup fact dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup fact [ add-choice ] callcc0 ] when
- dup number? [ 1+ (lookup-fact) ] [ 2nip extract-fact ] if ;
-
-: check-arity ( pattern fact -- pattern fact ? ) 2dup [ length ] 2apply = ;
-
-: check-elements ( pattern fact -- ? )
- t [ over var? [ 2drop t ] [ = ] if and ] 2reduce ;
-
-: match-pattern ( pattern fact -- ? )
- check-arity [ check-elements ] [ 2drop f ] if ;
-
-: good-result? ( pattern fact -- pattern fact ? )
- 2dup dup "No." = [ 2drop t ] [ match-pattern ] if ;
-
-: lookup-fact ( name pattern -- fact )
- swap 0 (lookup-fact) good-result? [ nip ] [ last-choice ] if ;
-
-: store-rule ( name pattern body -- ) 3array rules dup length swap set-nth ;
-
-: add-rule ( name pattern body -- ) store-rule ;
-
-: (lookup-rule) ( name num -- rule )
- dup rule dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup rule [ add-choice ] callcc0 ] when
- dup number? [ 1+ (lookup-rule) ] [ 2nip ] if ;
-
-: add-bindings ( pat-d pat-f binds -- binds )
- [ over var? over const? or
- [ 2drop ] [ swap 2array swap dup >r push r> ] if
- ] 2reduce ;
-
-: init-binds ( pat-d pat-f -- binds ) V{ } clone add-bindings >alist ;
-
-: deep-replace ( binds seq -- binds seq' )
- [ dup var? [ over 2dup key? [ at ] [ drop ] if ]
- [ dup sequence? [ dupd deep-replace nip ] when ] if
- ] map ;
-
-: backtrace? ( result -- )
- dup "No." = [ remove-choice last-choice ] [ [ last-choice ] unless* ] if ;
-
-: resolve-rule ( binds rules -- binds )
- [ deep-replace >quotation call backtrace? ] each ;
+++ /dev/null
-
-USING: kernel sequences arrays vectors namespaces math strings
- combinators continuations quotations io ;
-
-IN: prolog
-
-SYMBOL: pldb
-SYMBOL: plchoice
-
-: 2dupd ( x y z -- x y x y z ) >r 2dup r> ;
-
-: init-pl ( -- )
- V{ } clone V{ } clone 2array pldb set
- V{ } clone plchoice set ;
-
-: reset-choice ( -- ) V{ } clone plchoice set ;
-: remove-choice ( -- ) plchoice get pop drop ;
-
-: facts ( -- vector ) pldb get first ;
-: rules ( -- vector ) pldb get second ;
-: fact ( n -- fact ) dup facts length >= [ drop "No." ] [ facts nth ] if ;
-: rule ( n -- rule ) dup rules length >= [ drop "No." ] [ rules nth ] if ;
-
-: var? ( pl-obj -- ? )
- dup string? [ 0 swap nth LETTER? ] [ drop f ] if ;
-: const? ( pl-obj -- ? ) var? not ;
-
-: check-atom ( string -- ? ) const? ;
-
-: check-fact ( list -- list ? )
- dup t
- [ {
- { [ dup string? ] [ check-atom ] }
- { [ number? ] [ t ] }
- { [ t ] [ f ] }
- } cond and ] reduce ;
-
-: store-fact ( name fact -- ) 2array facts dup length swap set-nth ;
-
-: add-fact ( name fact -- )
- check-fact [ store-fact ] [ drop " not valid" append print ] if ;
-
-: add-choice ( continuation -- )
- dup continuation? [ plchoice get push ] [ drop ] if ;
-
-: last-choice ( -- ) plchoice get pop continue ;
-
-: extract-fact ( fact-entry -- fact ) dup string? [ 1 swap nth ] unless ;
-
-: (lookup-fact) ( name num -- fact )
- dup fact dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup fact [ ] callcc0 add-choice ] when
- dup number? [ 1+ (lookup-fact) ] [ 2nip extract-fact ] if ;
-
-: check-arity ( pattern fact -- pattern fact ? ) 2dup [ length ] 2apply = ;
-
-: check-elements ( pattern fact -- ? )
- [ over var? [ 2drop t ] [ = ] if ] 2all? ;
-
-: match-pattern ( pattern fact -- ? )
- check-arity [ check-elements ] [ 2drop f ] if ;
-
-: good-result? ( pattern fact -- pattern fact ? )
- 2dup dup "No." = [ 2drop t ] [ match-pattern ] if ;
-
-: lookup-fact ( name pattern -- fact )
- swap 0 (lookup-fact) good-result? [ nip ] [ last-choice ] if ;
-
-: store-rule ( name pattern body -- ) 3array rules dup length swap set-nth ;
-
-: add-rule ( name pattern body -- ) store-rule ;
-
-: (lookup-rule) ( name num -- pat-f rules )
- dup rule dup "No." = >r 0 swap nth swapd dupd = swapd r> or
- [ dup rule [ ] callcc0 add-choice ] when
- dup number? [ 1+ (lookup-rule) ] [ 2nip ] if ;
-
-: add-bindings ( pat-d pat-f binds -- binds )
- clone
- [ over var? over const? or
- [ 2drop ] [ rot dup >r set-at r> ] if
- ] 2reduce ;
-
-: init-binds ( pat-d pat-f -- binds ) V{ } clone add-bindings >alist ;
-
-: replace-if-bound ( binds elt -- binds elt' ) over 2dup key? [ at ] [ drop ] if ;
-
-: deep-replace ( binds seq -- binds seq' )
- [ dup var? [ replace-if-bound ]
- [ dup array? [ dupd deep-replace nip ] when ] if
- ] map ;
-
-: backtrace? ( result -- )
- dup "No." = [ remove-choice last-choice ]
- [ [ last-choice ] unless ] if ;
-
-: resolve-rule ( pat-d pat-f rule-body -- binds )
- >r 2dup init-binds r> [ deep-replace >quotation call dup backtrace?
- dup t = [ drop ] when ] each ;
-
-: rule>pattern ( rule -- pattern ) 1 swap nth ;
-: rule>body ( rule -- body ) 2 swap nth ;
-
-: binds>fact ( pat-d pat-f binds -- fact )
- [ 2dup key? [ at ] [ drop ] if ] curry map good-result?
- [ nip ] [ last-choice ] if ;
-
-: lookup-rule ( name pattern -- fact )
- swap 0 (lookup-rule) dup "No." =
- [ nip ]
- [
- dup rule>pattern swapd check-arity
- [ rot rule>body resolve-rule dup -roll binds>fact ] [ last-choice ] if
- ] if ;
-
-: resolve ( name pattern -- fact )
- 2dup lookup-fact dup "No." = [ drop lookup-rule ] [ 2nip ] if ;
-
-: binding-resolve ( binds name pattern -- binds )
- tuck lookup-fact dup backtrace? swap rot add-bindings ;
-
-! { { "A" "a" } { "B" "b" } } { { { "C" } "A" "B" = [ { "c" } ] [ { "d" } ] if rot add-bindings } }
projects / factor.git / commitdiff