Added an eval function and a run function. Eval currently only works …

…for Disp while run works for all.

Homework_1.sml

@@ -11,10 +11,29 @@ fun getB (m : MachineState) = #b m;
 fun setA (m : MachineState, newA) = newMachine(newA, #b m);
 fun setB (m : MachineState, newB) = newMachine(#a m, newB);
 
-(*Instruction Set*)
 datatype Instruction = SetA of int | SetB of int | Add | Sub | Disp;
+(*Converts Instruction to a string*)
 fun i2s (SetA a)	= "SetA " ^ Int.toString(a)
 	| i2s (SetB b)	= "SetB " ^ Int.toString(b)
 	| i2s Add		= "Add"
 	| i2s Sub		= "Sub"
 	| i2s Disp		= "Disp";
+
+(*Evaluates the given Instruction*)
+fun eval (m: MachineState, SetA a)	: MachineState = m;
+	| eval (m: MachineState, SetB b): MachineState = m;
+	| eval (m: MachineState, Add)	: MachineState = m;
+	| eval (m: MachineState, Sub)	: MachineState = m;
+	| eval (m: MachineState, Disp)	: MachineState = 
+		(print (Int.toString (#a m) ^ "\n"); m);
+
+(*Runs the list of Instructions*)
+fun run (m: MachineState, []: Instruction list) = m
+	| run (m: MachineState, prog: Instruction list) =
+		let val instr = hd prog
+			val instrs = tl prog
+			val _ = print (i2s instr ^ "\n");
+			val m1 = eval (m, instr);
+		in print (i2s instr ^ "\n");
+			run (m1: MachineState, tl prog : Instruction list)
+		end;