freebsd-dev/stand/ficl/softwords/classes.fr
2017-11-14 23:02:19 +00:00

174 lines
3.7 KiB
Forth

\ #if (FICL_WANT_OOP)
\ ** ficl/softwords/classes.fr
\ ** F I C L 2 . 0 C L A S S E S
\ john sadler 1 sep 98
\ Needs oop.fr
\
\ $FreeBSD$
also oop definitions
\ REF subclass holds a pointer to an object. It's
\ mainly for aggregation to help in making data structures.
\
object subclass c-ref
cell: .class
cell: .instance
: get ( inst class -- refinst refclass )
drop 2@ ;
: set ( refinst refclass inst class -- )
drop 2! ;
end-class
object subclass c-byte
char: .payload
: get drop c@ ;
: set drop c! ;
end-class
object subclass c-2byte
2 chars: .payload
: get drop w@ ;
: set drop w! ;
end-class
object subclass c-4byte
4 chars: .payload
: get drop q@ ;
: set drop q! ;
end-class
object subclass c-cell
cell: .payload
: get drop @ ;
: set drop ! ;
end-class
\ ** C - P T R
\ Base class for pointers to scalars (not objects).
\ Note: use c-ref to make references to objects. C-ptr
\ subclasses refer to untyped quantities of various sizes.
\ Derived classes must specify the size of the thing
\ they point to, and supply get and set methods.
\ All derived classes must define the @size method:
\ @size ( inst class -- addr-units )
\ Returns the size in address units of the thing the pointer
\ refers to.
object subclass c-ptr
c-cell obj: .addr
\ get the value of the pointer
: get-ptr ( inst class -- addr )
c-ptr => .addr
c-cell => get
;
\ set the pointer to address supplied
: set-ptr ( addr inst class -- )
c-ptr => .addr
c-cell => set
;
\ force the pointer to be null
: clr-ptr
0 -rot c-ptr => .addr c-cell => set
;
\ return flag indicating null-ness
: ?null ( inst class -- flag )
c-ptr => get-ptr 0=
;
\ increment the pointer in place
: inc-ptr ( inst class -- )
2dup 2dup ( i c i c i c )
c-ptr => get-ptr -rot ( i c addr i c )
--> @size + -rot ( addr' i c )
c-ptr => set-ptr
;
\ decrement the pointer in place
: dec-ptr ( inst class -- )
2dup 2dup ( i c i c i c )
c-ptr => get-ptr -rot ( i c addr i c )
--> @size - -rot ( addr' i c )
c-ptr => set-ptr
;
\ index the pointer in place
: index-ptr { index 2:this -- }
this --> get-ptr ( addr )
this --> @size index * + ( addr' )
this --> set-ptr
;
end-class
\ ** C - C E L L P T R
\ Models a pointer to cell (a 32 or 64 bit scalar).
c-ptr subclass c-cellPtr
: @size 2drop 1 cells ;
\ fetch and store through the pointer
: get ( inst class -- cell )
c-ptr => get-ptr @
;
: set ( value inst class -- )
c-ptr => get-ptr !
;
end-class
\ ** C - 4 B Y T E P T R
\ Models a pointer to a quadbyte scalar
c-ptr subclass c-4bytePtr
: @size 2drop 4 ;
\ fetch and store through the pointer
: get ( inst class -- value )
c-ptr => get-ptr q@
;
: set ( value inst class -- )
c-ptr => get-ptr q!
;
end-class
\ ** C - 2 B Y T E P T R
\ Models a pointer to a 16 bit scalar
c-ptr subclass c-2bytePtr
: @size 2drop 2 ;
\ fetch and store through the pointer
: get ( inst class -- value )
c-ptr => get-ptr w@
;
: set ( value inst class -- )
c-ptr => get-ptr w!
;
end-class
\ ** C - B Y T E P T R
\ Models a pointer to an 8 bit scalar
c-ptr subclass c-bytePtr
: @size 2drop 1 ;
\ fetch and store through the pointer
: get ( inst class -- value )
c-ptr => get-ptr c@
;
: set ( value inst class -- )
c-ptr => get-ptr c!
;
end-class
previous definitions
\ #endif