[gforth] / gforth / objects.fs  

gforth: gforth/objects.fs

Diff for /gforth/objects.fs between version 1.6 and 1.18

version 1.6, Thu Jul 31 16:17:10 1997 UTC version 1.18, Wed Aug 23 21:03:52 2000 UTC
Line 1 
Line 1 
 \ yet another Forth objects extension  \ yet another Forth objects extension
   
 \ written by Anton Ertl 1996, 1997  \ written by Anton Ertl 1996-1999
 \ public domain; NO WARRANTY  \ public domain; NO WARRANTY
   
 \ This (in combination with compat/struct.fs) is in ANS Forth (with an  \ This (in combination with compat/struct.fs) is in ANS Forth (with an
Line 96 
Line 96 
 interface%  interface%
     cell%    field class-parent      cell%    field class-parent
     cell%    field class-wordlist \ inst-vars and other protected words      cell%    field class-wordlist \ inst-vars and other protected words
     cell% 2* field class-inst-size ( class -- addr ) \ objects      cell% 2* field class-inst-size ( class -- addr ) \ objects- objects
     \g used as @code{class-inst-size 2@ ( class -- align size )},      \g Give the size specification for an instance (i.e. an object)
     \g gives the size specification for an instance (i.e. an object)      \g of @var{class};
     \g of @code{class}.      \g used as @code{class-inst-size 2@ ( class -- align size )}.
 end-struct class%  end-struct class%
   
 struct  struct
Line 118 
Line 118 
   
 \ selectors and methods  \ selectors and methods
   
 variable current-interface ( -- addr ) \ objects  variable current-interface ( -- addr ) \ objects- objects
 \g this variable contains the class or interface currently being  \g Variable: contains the class or interface currently being
 \g defined.  \g defined.
   
   
Line 139 
Line 139 
     swap object-map @ + @ ( object selector-body map )      swap object-map @ + @ ( object selector-body map )
     swap selector-offset @ + perform ;      swap selector-offset @ + perform ;
   
 : method ( xt "name" -- ) \ objects  : method ( xt "name" -- ) \ objects- objects
     \g @code{name} execution: @code{... object -- ...}@*      \g @code{name} execution: @code{... object -- ...}@*
     \g creates selector @code{name} and makes @code{xt} its method in      \g Create selector @var{name} and makes @var{xt} its method in
     \g the current class.      \g the current class.
     create      create
     current-interface @ interface-map 2@ ( xt map-addr map-size )      current-interface @ interface-map 2@ ( xt map-addr map-size )
Line 154 
Line 154 
         do-class-method          do-class-method
     then ;      then ;
   
 : selector ( "name" -- ) \ objects  : selector ( "name" -- ) \ objects- objects
     \g @code{name} execution: @code{... object -- ...}@*      \g @var{name} execution: @code{... object -- ...}@*
     \g creates selector @code{name} for the current class and its      \g Create selector @var{name} for the current class and its
     \g descendents; you can set a method for the selector in the      \g descendents; you can set a method for the selector in the
     \g current class with @code{overrides}.      \g current class with @code{overrides}.
     ['] no-method method ;      ['] no-method method ;
Line 166 
Line 166 
     swap >body ( xt map selector-body )      swap >body ( xt map selector-body )
     selector-offset @ + ! ;      selector-offset @ + ! ;
   
 : class->map ( class -- map ) \ objects  : class->map ( class -- map ) \ objects- objects
     \g @code{map} is the pointer to @code{class}'s method map; it      \g @var{map} is the pointer to @var{class}'s method map; it
     \g points to the place in the map to which the selector offsets      \g points to the place in the map to which the selector offsets
     \g refer (i.e., where @code{object-map}s point to).      \g refer (i.e., where @var{object-map}s point to).
     dup interface-map 2@ drop swap interface-map-offset @ + ;      dup interface-map 2@ drop swap interface-map-offset @ + ;
   
 : unique-interface-map ( class-map offset -- )  : unique-interface-map ( class-map offset -- )
Line 177 
Line 177 
     \ copy it to make it unique; used for implementing a copy-on-write policy      \ copy it to make it unique; used for implementing a copy-on-write policy
     over @ class-parent @ class->map ( class-map offset parent-map )      over @ class-parent @ class->map ( class-map offset parent-map )
     over + @ >r  \ the map for the interface for the parent      over + @ >r  \ the map for the interface for the parent
     + dup @ ( mapp map )      + dup @ ( interface-mapp interface-map )
     dup r> =      dup r> =
     if      if
         @ interface-map 2@ save-mem drop          dup @ interface-map 2@ nip save-mem drop
         swap !          swap !
     else      else
         2drop          2drop
     then ;      then ;
   
 : class-override! ( xt sel-xt class-map -- ) \ objects  : class-override! ( xt sel-xt class-map -- ) \ objects- objects
     \g @code{xt} is the new method for the selector @code{sel-xt} in      \g @var{xt} is the new method for the selector @var{sel-xt} in
     \g @code{class-map}.      \g @var{class-map}.
     over >body ( xt sel-xt class-map selector-body )      over >body ( xt sel-xt class-map selector-body )
     selector-interface @ ( xt sel-xt class-map offset )      selector-interface @ ( xt sel-xt class-map offset )
     ?dup-if \ the selector is for an interface      ?dup-if \ the selector is for an interface
Line 197 
Line 197 
     then      then
     interface-override! ;      interface-override! ;
   
 : overrides ( xt "selector" -- ) \ objects  : overrides ( xt "selector" -- ) \ objects- objects
     \g replace default method for @code{selector} in the current class      \g replace default method for @var{selector} in the current class
     \g with @code{xt}. @code{overrides} must not be used during an      \g with @var{xt}. @code{overrides} must not be used during an
     \g interface definition.      \g interface definition.
     ' current-interface @ class->map class-override! ;      ' current-interface @ class->map class-override! ;
   
Line 208 
Line 208 
 \ every interface gets a different offset; the latest one is stored here  \ every interface gets a different offset; the latest one is stored here
 variable last-interface-offset 0 last-interface-offset !  variable last-interface-offset 0 last-interface-offset !
   
 : interface ( -- ) \ objects  : interface ( -- ) \ objects- objects
     \g starts an interface definition.      \g Start an interface definition.
     interface% %allot >r      interface% %allot >r
     0 0 r@ interface-map 2!      r@ current-interface !
       current-interface 1 cells save-mem r@ interface-map 2!
     -1 cells last-interface-offset +!      -1 cells last-interface-offset +!
     last-interface-offset @ r@ interface-offset !      last-interface-offset @ r@ interface-offset !
     0 r@ interface-map-offset !      0 r> interface-map-offset ! ;
     r> current-interface ! ;  
   
 : end-interface-noname ( -- interface ) \ objects  : end-interface-noname ( -- interface ) \ objects- objects
     \g ends an interface definition. The resulting interface is      \g End an interface definition. The resulting interface is
     \g @code{interface}.      \g @var{interface}.
     current-interface @ ;      current-interface @ ;
   
 : end-interface ( "name" -- ) \ objects  : end-interface ( "name" -- ) \ objects- objects
     \g @code{name} execution: @code{-- interface}@*      \g @code{name} execution: @code{-- interface}@*
     \g ends an interface definition. The resulting interface is      \g End an interface definition. The resulting interface is
     \g @code{interface}.      \g @var{interface}.
     end-interface-noname constant ;      end-interface-noname constant ;
   
   \ visibility control
   
   variable public-wordlist
   
   : protected ( -- ) \ objects- objects
       \g Set the compilation wordlist to the current class's wordlist
       current-interface @ class-wordlist @
       dup get-current <>
       if \ we are not protected already
           get-current public-wordlist !
       then
       set-current ;
   
   : public ( -- ) \ objects- objects
       \g Restore the compilation wordlist that was in effect before the
       \g last @code{protected} that actually changed the compilation
       \g wordlist.
       current-interface @ class-wordlist @ get-current =
       if \ we are protected
           public-wordlist @ set-current
       then ;
   
 \ classes  \ classes
   
 : add-class-order ( n1 class -- wid1 ... widn n+n1 )  : add-class-order ( n1 class -- wid1 ... widn n+n1 )
Line 237 
Line 259 
     then      then
     r> class-wordlist @ swap 1+ ;      r> class-wordlist @ swap 1+ ;
   
 : push-order ( class -- ) \ objects  : class>order ( class -- ) \ objects- objects
     \g add @code{class}'s wordlists to the search-order (in front)      \g Add @var{class}'s wordlists to the head of the search-order.
     >r get-order r> add-class-order set-order ;      >r get-order r> add-class-order set-order ;
   
 : class ( parent-class -- align offset ) \ objects  : push-order class>order ; \ old name
     \g start a new class definition as a child of  
     \g @code{parent-class}. @code{align offset} are for use by  : methods ( class -- ) \ objects- objects
     \g @code{field} etc.      \g Makes @var{class} the current class. This is intended to be
       \g used for defining methods to override selectors; you cannot
       \g define new fields or selectors.
       dup current-interface ! class>order ;
   
   : class ( parent-class -- align offset ) \ objects- objects
       \g Start a new class definition as a child of
       \g @var{parent-class}. @var{align offset} are for use by
       \g @var{field} etc.
     class% %allot >r      class% %allot >r
     dup interface-map 2@ save-mem r@ interface-map 2!      dup interface-map 2@ save-mem r@ interface-map 2!
     dup interface-map-offset @ r@ interface-map-offset !      dup interface-map-offset @ r@ interface-map-offset !
Line 252 
Line 282 
     0 r@ interface-offset !      0 r@ interface-offset !
     dup r@ class-parent !      dup r@ class-parent !
     wordlist r@ class-wordlist !      wordlist r@ class-wordlist !
     r@ current-interface !      r> methods
     r> push-order  
     class-inst-size 2@ ;      class-inst-size 2@ ;
   
 : remove-class-order ( wid1 ... widn n+n1 class -- n1 )  : remove-class-order ( wid1 ... widn n+n1 class -- n1 )
Line 264 
Line 293 
     until      until
     drop ;      drop ;
   
 : drop-order ( class -- ) \ objects  : class-previous ( class -- ) \ objects- objects
     \g drops @code{class}'s wordlists from the search order. No      \g Drop @var{class}'s wordlists from the search order. No
     \g checking is made whether @code{class}'s wordlists are actually      \g checking is made whether @var{class}'s wordlists are actually
     \g on the search order.      \g on the search order.
     >r get-order r> remove-class-order set-order ;      >r get-order r> remove-class-order set-order ;
   
 : end-class-noname ( align offset -- class ) \ objects  : drop-order class-previous ; \ old name
     \g ends a class definition. The resulting class is @code{class}.  
     current-interface @ dup drop-order class-inst-size 2!  : end-methods ( -- ) \ objects- objects
       \g Switch back from defining methods of a class to normal mode
       \g (currently this just restores the old search order).
       current-interface @ class-previous ;
   
   : end-class-noname ( align offset -- class ) \ objects- objects
       \g End a class definition. The resulting class is @var{class}.
       public end-methods
       current-interface @ class-inst-size 2!
     end-interface-noname ;      end-interface-noname ;
   
 : end-class ( align offset "name" -- ) \ objects  : end-class ( align offset "name" -- ) \ objects- objects
     \g @code{name} execution: @code{-- class}@*      \g @var{name} execution: @code{-- class}@*
     \g ends a class definition. The resulting class is @code{class}.      \g End a class definition. The resulting class is @var{class}.
     \ name execution: ( -- class )      \ name execution: ( -- class )
     end-class-noname constant ;      end-class-noname constant ;
   
 \ visibility control  
   
 variable public-wordlist  
   
 : protected ( -- ) \ objects  
     \g set the compilation wordlist to the current class's wordlist  
     current-interface @ class-wordlist @  
     dup get-current <>  
     if \ we are not protected already  
         get-current public-wordlist !  
     then  
     set-current ;  
   
 : public ( -- ) \ objects  
     \g restore the compilation wordlist that was in effect before the  
     \g last @code{protected} that actually changed the compilation  
     \g wordlist.  
     public-wordlist @ set-current ;  
   
 \ classes that implement interfaces  \ classes that implement interfaces
   
 : front-extend-mem ( addr1 u1 u -- addr addr2 u2 )  : front-extend-mem ( addr1 u1 u -- addr addr2 u2 )
     \ extend memory block allocated from the heap by u aus, with the      \ Extend memory block allocated from the heap by u aus, with the
     \ old stuff coming at the end      \ old stuff coming at the end
     2dup + dup >r allocate throw ( addr1 u1 u addr2 ; R: u2 )      2dup + dup >r allocate throw ( addr1 u1 u addr2 ; R: u2 )
     dup >r + >r over r> rot move ( addr1 ; R: u2 addr2 )      dup >r + >r over r> rot move ( addr1 ; R: u2 addr2 )
     free throw      free throw
     r> dup r> ;      r> dup r> ;
   
 : implementation ( interface -- ) \ objects  : implementation ( interface -- ) \ objects- objects
     \g the current class implements @code{interface}. I.e., you can      \g The current class implements @var{interface}. I.e., you can
     \g use all selectors of the interface in the current class and its      \g use all selectors of the interface in the current class and its
     \g descendents.      \g descendents.
     dup interface-offset @ ( interface offset )      dup interface-offset @ ( interface offset )
Line 332 
Line 350 
 \ this/self, instance variables etc.  \ this/self, instance variables etc.
   
 \ rename "this" into "self" if you are a Smalltalk fiend  \ rename "this" into "self" if you are a Smalltalk fiend
 0 value this ( -- object ) \ objects  0 value this ( -- object ) \ objects- objects
 \g the receiving object of the current method (aka active object).  \g the receiving object of the current method (aka active object).
 : to-this ( object -- ) \ objects  : to-this ( object -- ) \ objects- objects
     \g sets @code{this} (used internally, but useful when debugging).      \g Set @code{this} (used internally, but useful when debugging).
     TO this ;      TO this ;
   
 \ another implementation, if you don't have (fast) values  \ another implementation, if you don't have (fast) values
Line 345 
Line 363 
 \ : to-this ( object -- )  \ : to-this ( object -- )
 \     thisp ! ;  \     thisp ! ;
   
 : m: ( -- xt colon-sys; run-time: object -- ) \ objects  : enterm ( -- ; run-time: object -- )
     \g start a method definition; @code{object} becomes new @code{this}.      \g method prologue; @var{object} becomes new @code{this}.
     :noname  
     POSTPONE this      POSTPONE this
     POSTPONE >r      POSTPONE >r
     POSTPONE to-this ;      POSTPONE to-this ;
   
 : exitm ( -- ) \ objects  : m: ( -- xt colon-sys; run-time: object -- ) \ objects- objects
       \g Start a method definition; @var{object} becomes new @code{this}.
       :noname enterm ;
   
   : :m ( "name" -- xt; run-time: object -- ) \ objects- objects
       \g Start a named method definition; @var{object} becomes new
       \g @code{this}.  Has to be ended with @code{;m}.
       : enterm ;
   
   : exitm ( -- ) \ objects- objects
     \g @code{exit} from a method; restore old @code{this}.      \g @code{exit} from a method; restore old @code{this}.
     POSTPONE r>      POSTPONE r>
     POSTPONE to-this      POSTPONE to-this
     POSTPONE exit ; immediate      POSTPONE exit ; immediate
   
 : ;m ( colon-sys --; run-time: -- ) \ objects  : ;m ( colon-sys --; run-time: -- ) \ objects- objects
     \g end a method definition; restore old @code{this}.      \g End a method definition; restore old @code{this}.
     POSTPONE r>      POSTPONE r>
     POSTPONE to-this      POSTPONE to-this
     POSTPONE ; ; immediate      POSTPONE ; ; immediate
   
 : catch ( ... xt -- ... n )  : catch ( ... xt -- ... n ) \ exception
     \ make it safe to call CATCH within a method.      \ Make it safe to call CATCH within a method.
     \ should also be done with all words containing CATCH.      \ should also be done with all words containing CATCH.
     this >r catch r> to-this ;      this >r catch r> to-this ;
   
Line 384 
Line 410 
 does> \ name execution: ( -- addr )  does> \ name execution: ( -- addr )
     ( addr1 ) @ this + ;      ( addr1 ) @ this + ;
   
 : inst-var ( align1 offset1 align size "name" -- align2 offset2 ) \ objects  : inst-var ( align1 offset1 align size "name" -- align2 offset2 ) \ objects- objects
     \g @code{name} execution: @code{-- addr}@*      \g @var{name} execution: @code{-- addr}@*
     \g @code{addr} is the address of the field @code{name} in      \g @var{addr} is the address of the field @var{name} in
     \g @code{this} object.      \g @code{this} object.
     ['] do-inst-var inst-something ;      ['] do-inst-var inst-something ;
   
Line 394 
Line 420 
 does> \ name execution: ( -- w )  does> \ name execution: ( -- w )
     ( addr1 ) @ this + @ ;      ( addr1 ) @ this + @ ;
   
 : inst-value ( align1 offset1 "name" -- align2 offset2 ) \ objects  : inst-value ( align1 offset1 "name" -- align2 offset2 ) \ objects- objects
     \g @code{name} execution: @code{-- w}@*      \g @var{name} execution: @code{-- w}@*
     \g @code{w} is the value of the field @code{name} in @code{this}      \g @var{w} is the value of the field @var{name} in @code{this}
     \g object.      \g object.
     cell% ['] do-inst-value inst-something ;      cell% ['] do-inst-value inst-something ;
   
 : <to-inst> ( w xt -- ) \ objects  : <to-inst> ( w xt -- ) \ objects- objects
     \g store @code{w} into the field @code{xt} in @code{this} object.      \g store @var{w} into the field @var{xt} in @code{this} object.
     >body @ this + ! ;      >body @ this + ! ;
   
 : [to-inst] ( compile-time: "name" -- ; run-time: w -- ) \ objects  : [to-inst] ( compile-time: "name" -- ; run-time: w -- ) \ objects- objects
     \g store @code{w} into field @code{name} in @code{this} object.      \g store @var{w} into field @var{name} in @code{this} object.
     ' >body @ POSTPONE literal      ' >body @ POSTPONE literal
     POSTPONE this      POSTPONE this
     POSTPONE +      POSTPONE +
Line 413 
Line 439 
   
 \ class binding stuff  \ class binding stuff
   
 : <bind> ( class selector-xt -- xt ) \ objects  : <bind> ( class selector-xt -- xt ) \ objects- objects
     \g @code{xt} is the method for the selector @code{selector-xt} in      \g @var{xt} is the method for the selector @var{selector-xt} in
     \g @code{class}.      \g @var{class}.
     >body swap class->map over selector-interface @      >body swap class->map over selector-interface @
     ?dup-if      ?dup-if
         + @          + @
     then      then
     swap selector-offset @ + @ ;      swap selector-offset @ + @ ;
   
 : bind' ( "class" "selector" -- xt ) \ objects  : bind' ( "class" "selector" -- xt ) \ objects- objects
     \g @code{xt} is the method for @code{selector} in @code{class}.      \g @var{xt} is the method for @var{selector} in @var{class}.
     ' execute ' <bind> ;      ' execute ' <bind> ;
   
 : bind ( ... "class" "selector" -- ... ) \ objects  : bind ( ... "class" "selector" -- ... ) \ objects- objects
     \g execute the method for @code{selector} in @code{class}.      \g Execute the method for @var{selector} in @var{class}.
     bind' execute ;      bind' execute ;
   
 : [bind] ( compile-time: "class" "selector" -- ; run-time: ... object -- ... ) \ objects  : [bind] ( compile-time: "class" "selector" -- ; run-time: ... object -- ... ) \ objects- objects
     \g compile the method for @code{selector} in @code{class}.      \g Compile the method for @var{selector} in @var{class}.
     bind' compile, ; immediate      bind' compile, ; immediate
   
 : current' ( "selector" -- xt ) \ objects  : current' ( "selector" -- xt ) \ objects- objects
     \g @code{xt} is the method for @code{selector} in the current class.      \g @var{xt} is the method for @var{selector} in the current class.
     current-interface @ ' <bind> ;      current-interface @ ' <bind> ;
   
 : [current] ( compile-time: "selector" -- ; run-time: ... object -- ... ) \ objects  : [current] ( compile-time: "selector" -- ; run-time: ... object -- ... ) \ objects- objects
     \g compile the method for @code{selector} in the current class.      \g Compile the method for @var{selector} in the current class.
     current' compile, ; immediate      current' compile, ; immediate
   
 : [parent] ( compile-time: "selector" -- ; run-time: ... object -- ... ) \ objects  : [parent] ( compile-time: "selector" -- ; run-time: ... object -- ... ) \ objects- objects
     \g compile the method for @code{selector} in the parent of the      \g Compile the method for @var{selector} in the parent of the
     \g current class.      \g current class.
     current-interface @ class-parent @ ' <bind> compile, ; immediate      current-interface @ class-parent @ ' <bind> compile, ; immediate
   
Line 459 
Line 485 
 0 current-interface @ class-parent !  0 current-interface @ class-parent !
 wordlist current-interface @ class-wordlist !  wordlist current-interface @ class-wordlist !
 object%  object%
 current-interface @ push-order  current-interface @ class>order
   
 ' drop ( object -- )  ' drop ( object -- )
 method construct ( ... object -- ) \ objects  method construct ( ... object -- ) \ objects- objects
 \g initializes the data fields of @code{object}. The method for the  \g Initialize the data fields of @var{object}. The method for the
 \g class @code{object} just does nothing @code{( object -- )}.  \g class @var{object} just does nothing: @code{( object -- )}.
   
 :noname ( object -- )  :noname ( object -- )
     ." object:" dup . ." class:" object-map @ @ . ;      ." object:" dup . ." class:" object-map @ @ . ;
 method print ( object -- ) \ objects  method print ( object -- ) \ objects- objects
 \g prints the object. The method for the class @code{object} prints  \g Print the object. The method for the class @var{object} prints
 \g the address of the object and the address of its class.  \g the address of the object and the address of its class.
   
 end-class object ( -- class ) \ objects  selector equal ( object1 object2 -- flag )
   
   end-class object ( -- class ) \ objects- objects
 \g the ancestor of all classes.  \g the ancestor of all classes.
   
 \ constructing objects  \ constructing objects
   
 : init-object ( ... class object -- ) \ objects  : init-object ( ... class object -- ) \ objects- objects
     \g initializes a chunk of memory (@code{object}) to an object of      \g Initialize a chunk of memory (@var{object}) to an object of
     \g class @code{class}; then performs @code{construct}.      \g class @var{class}; then performs @code{construct}.
     swap class->map over object-map ! ( ... object )      swap class->map over object-map ! ( ... object )
     construct ;      construct ;
   
 : xt-new ( ... class xt -- object ) \ objects  : xt-new ( ... class xt -- object ) \ objects- objects
     \g makes a new object, using @code{xt ( align size -- addr )} to      \g Make a new object, using @code{xt ( align size -- addr )} to
     \g get memory.      \g get memory.
     over class-inst-size 2@ rot execute      over class-inst-size 2@ rot execute
     dup >r init-object r> ;      dup >r init-object r> ;
   
 : dict-new ( ... class -- object ) \ objects  : dict-new ( ... class -- object ) \ objects- objects
     \g @code{allot} and initialize an object of class @code{class} in      \g @code{allot} and initialize an object of class @var{class} in
     \g the dictionary.      \g the dictionary.
     ['] %allot xt-new ;      ['] %allot xt-new ;
   
 : heap-new ( ... class -- object ) \ objects  : heap-new ( ... class -- object ) \ objects- objects
     \g @code{allocate} and initialize an object of class @code{class}.      \g @code{allocate} and initialize an object of class @var{class}.
     ['] %alloc xt-new ;      ['] %alloc xt-new ;

Generate output suitable for use with a patch program
Legend:
Removed from v.1.6  
changed lines
  Added in v.1.18
CVS Admin

Powered by ViewCVS 1.0-dev 		(Powered by ViewCVS)

ViewCVS and CVS Help