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macro PRINT String{

        local .Printer
        local .Nextchar
        local .Done
        local .a

        .Printer:
                mov si, .a
                mov ah, 0Eh
                jmp .Nextchar

        .Nextchar:
                lodsb
                or al, al
                jz .Done
                int 10h
                jmp .Nextchar
                jmp .Done

        .a db String,10,13,0

        .Done:
}  

macro SCREEN mode
{
	push ax

	if mode = 0
		mov ah,0h		;SCREEN 0; Default DOS screen mode
		mov al,3h
		int 10h
	else if mode = 13
		mov ah,0h		;SCREEN 13; VGA
		mov al,13h
		int 10h
	end if

	pop ax
}

macro SLEEP
{
	;Output:
	;ah = BIOS scancode of key pressed
	;al = ASCII character of key pressed
	;Could have also used...
	;	mov ah,8h
	;	int 21h
	mov ah,0h
	int 16h
}

macro END
{
	mov ax,4Ch	;\END
	int 21h		;/
}

macro LOCATE row,col
{
	pusha

	mov ah,2		;Function 2
	mov bh,0		;Use page 0
	mov dh,row	;row
	mov dl,col		;col
	int 10h

	popa
}

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	SCREEN 0
	COLOR 33
	LOCATE 5,5
	PRINT "Hello World"
	SLEEP
	END

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macro case op1,op2
	{
	cmp  byte [edx],op1
	je   op2
	}

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;;---------------------------------------------------------;;
;;  - Solidus117
;;		Team DexOS
;; Interpret                                              
;;   Interpret the Brainfuck source, acting upon the VMM  
;;---------------------------------------------------------;;
	Interpret:
		mov  edx,loadpoint-1
		mov  ebx,memory

	lp:	inc  edx
		case '+',incval
		case '-',decval
		case '>',incptr
		case '<',decptr
		case '.',putval
		case ',',getval
		case '[',tstjmp
		case ']',uncjmp
		case 00h,@f
		jmp  lp
	@@:	ret

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  ... constant expressions are always calculated
  from left to right, contrary to the usual rules of arithmetic. This is
  unlike the situation in other computer languages, and you must be careful
  when writing expressions to remember that 2+3*2 equals 10 and not 8.

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(+ 4 (* a b) 5) = 4+ a*b + 5