copied asm here so that stays working while i break (an) arm

lib/arm/instruction.rb

@@ -0,0 +1,46 @@
+require_relative "assembly_error"
+require_relative "arm_machine"
+
+module Asm
+
+  class Code ; end
+  
+  # Not surprisingly represents an cpu instruction. 
+  # This is an abstract base class, with derived classes 
+  # Logic / Move / Compare / Stack / Memory (see there)
+  # 
+  # Opcode is a (<= three) letter accronym (same as in assembly code). Though in arm, suffixes can
+  # make the opcode longer, we chop those off in the constructor
+  # Argurments are registers or labels or string/num Literals
+  
+  class Instruction < Code
+    include ArmMachine
+
+    COND_POSTFIXES = Regexp.union( COND_CODES.keys.collect{|k|k.to_s} ).source
+
+    def initialize(opcode , condition_code , update_status , args)
+      @update_status_flag = update_status
+      @condition_code = condition_code.to_sym
+      @opcode = opcode
+      @args = args
+      @operand = 0
+    end
+    
+    attr_reader :opcode, :args 
+    # Many arm instructions may be conditional, where the default condition is always (al)
+    # ArmMachine::COND_CODES names them, and this attribute reflects it
+    attr_reader :condition_code
+    attr_reader :operand
+
+    # Logic instructions may be executed with or without affecting the status register
+    # Only when an instruction affects the status is a subsequent compare instruction effective
+    # But to make the conditional execution (see cond) work for more than one instruction, one needs to
+    # be able to execute without changing the status 
+    attr_reader :update_status_flag
+    
+    # arm intrucioons are pretty sensible, and always 4 bytes (thumb not supported)
+    def length
+      4
+    end
+  end
+end