if_any(Reg, Types, Body) ->
    [{push, [false]},
     [[{push, [Reg, T]}, strict_equals, 'or'] || T <- Types],
     'not',
     {'if', Body}].

define_regs() ->
    [{push, ["_r0", "_r1", "_r2", "_r3"]},
     define_local2,
     define_local2,
     define_local2,
     define_local2].

with_regs(L) ->
    [{push, ["_r0", r0]}, set_variable,
     {push, ["_r1", r1]}, set_variable,
     {push, ["_r2", r2]}, set_variable,
     {push, ["_r3", r3]}, set_variable,
     L,
     {store_register, 0, [{get_variable, "_r0"}]},
     {store_register, 1, [{get_variable, "_r1"}]},
     {store_register, 2, [{get_variable, "_r2"}]},
     {store_register, 3, [{get_variable, "_r3"}]}].

json_function() ->
    Recurse = with_regs([{push, [1]},
			 {get_variable, "arguments"},
			 {push, ["callee"]},
			 call_method]),
    {define_function, "", ["arg"],
     [% var lut = "0123456789abcdef";
      {push, ["lut", "0123456789abcdef"]},
      define_local,
      
      % var _r0, _r1, _r2, _r3;
      define_regs(),
      
      % r0 = arg;
      {store_register, 0, [{get_variable, "arg"}]},

      % r1 = typeof(r0);
      {store_register, 1, [{push, [r0]}, typeof]},

      % if (!!(r0 === undefined || r0 === null)) { return "null"; }
      if_any(r0, [null, undefined],
	     [{push, ["null"]},
	      return]),

      % if (!!(r1 == "number" || r1 == "boolean")) { return r0.toString(); }
      if_any(r1, ["number", "boolean"],
	     [{push, [r0]},
	      to_string,
	      return]),

      % if (!!(r1 == "movieclip" || r1 == "function")) { ... }
      if_any(r1, ["movieclip", "function"],
	     [% r0 = r1.toString();
	      {store_register, 0, [{push, [r0]},
				   to_string]},
	      % r1 = "string";
	      {store_register, 1, [{push, ["string"]}]}]),

      % r3 = new Array();
      {store_register, 3, [{new_object, "Array"}]},

      % if (!!(r1 == "string")) { ... }
      if_any(r1, ["string"],
	     [% r2 = r0.length;
	      {store_register, 2,
	       [{push, [r0, "length"]},
		get_member]},
	      
	      % if (!r2) { return "\"\""; }
	      {push, [r2]},
	      {'if',
	       [{push, ["\"\""]},
		return]},
		
	      % do { ... } while (r2)
	      {dowhile, 
	       [% r2 -= 1;
		{store_register, 2,
		 [{push, [r2]},
		  decrement]},
		  
		% r1 = r0.charAt(r2);
		{store_register, 1,
		 [{push, [r2, 1, r0, "charAt"]},
		  call_method]},
		
		% if (r1 === "\b") r1 = "\\b";
		if_any(r1, ["\b"],
		       [{store_register, 1, [{push, ["\\b"]}]}]),

		% if (r1 === "\f") r1 = "\\f";
		if_any(r1, ["\f"],
		       [{store_register, 1, [{push, ["\\f"]}]}]),

		% if (r1 === "\n") r1 = "\\n";
		if_any(r1, ["\n"],
		       [{store_register, 1, [{push, ["\\n"]}]}]),

		% if (r1 === "\r") r1 = "\\r";
		if_any(r1, ["\r"],
		       [{store_register, 1, [{push, ["\\r"]}]}]),

		% if (r1 === "\t") r1 = "\\t";
		if_any(r1, ["\t"],
		       [{store_register, 1, [{push, ["\\t"]}]}]),

		% if (r1 === "\"" || r1 === "\\" || r1 === "/") { ... }
		if_any(r1, ["\"", "\\", "/"],
		       [% r1 = "\\" + r1;
			{store_register, 1,
			 [{push, ["\\", r1]}, string_add]}]),
  		
		% if (!!(r1 < ' ' || '~' < r1)) { ... }
		{push, [r1, " "]},
		string_less,
		{push, ["~", r1]},
		string_less,
		'or',
		'not',
		{'if',
		 [% r1 = r0.charCodeAt(r2);
		  {store_register, 1,
		   [{push, [r2, 1, r0, "charCodeAt"]},
		    call_method]},
		  
		  % r1 = "\\u" + 
		  %      lut[(r1 >> 24) & 15] +
		  %      lut[(r1 >> 16) & 15] +
		  %      lut[(r1 >> 8) & 15] +
		  %      lut[r1 & 15];
		  {store_register, 1,
		   [{push, ["\\u"]},
		    {get_variable, "lut"},
		    {push, [15, r1, 24]}, bit_urshift, bit_and, get_member,
		    {get_variable, "lut"},
		    {push, [15, r1, 16]}, bit_urshift, bit_and, get_member,
		    {get_variable, "lut"},
		    {push, [15, r1, 8]}, bit_urshift, bit_and, get_member,
		    {get_variable, "lut"},
		    {push, [15, r1]}, bit_and, get_member,
		    string_add,
		    string_add,
		    string_add,
		    string_add]}]},

		% r3[r2] = r1;
		{push, [r3, r2, r1]},
		set_member,

		% ... while (r2)
		{push, [r2]}]},
			
	      % r3 = r3.join("");
	      {store_register, 3,
	       [{push, ["", 1, r3, "join"]}, call_method]},
		
	      % return "\"" + r3 + "\"";
	      {push, ["\"", r3, "\""]},
	      string_add,
	      string_add,
	      return]),

      % if (!!(r0 instanceof Array)) { ... }
      {push, [r0, "Array"]},
      get_variable,
      instance_of,
      'not',
      {'if',
       [% r2 = r0.length;
	{store_register, 2,
	 [{push, [r0, "length"]},
	  get_member]},
        
        % if (!!r2) { ... }
	{push, [r2]},
	'not',
	{'if', 
	 [% do { ... } while (r2)
	  {dowhile, 
	   [% r2 -= 1;
	    {store_register, 2,
	     [{push, [r2]},
	      decrement]},
	    
	    % r1 = fn(fn, r0[r2]);
	    {store_register, 1,
	     [{push, [r0, r2]},
	      get_member | Recurse]},

	    % r3[r2] = r1;
	    {push, [r3, r2, r1]},
	    set_member,

	    % ... while (r2)
	    {push, [r2]}]}]},
	
	% r3 = r3.join(",");
	{store_register, 3,
	 [{push, [",", 1, r3, "join"]},
	  call_method]},

	% return "[" + r3 + "]";
	{push, ["[", r3, "]"]},
	string_add,
	string_add,
	return]},

      % r2 = 0;
      {store_register, 2,
       [{push, [0]}]},
      
      % for (stack in r0) { ... }
      {push, [r0]},
      {enumerate,
       [% r1 = stack; // no pop
	{store_register, 1},

	% r3[r2] = fn(fn, r1) + ":" + fn(fn, r0[r1]);
	{push, [r3, r2]},
	[{push, [r1]} | Recurse],
	{push, [":"]},
	[{push, [r0, r1]}, get_member | Recurse],
	string_add,
	string_add,
	set_member,
	
	% r2 += 1;
	{store_register, 2,
	 [{push, [r2]},
	  increment]}]},
      
      % r3 = r3.join(",");
      {store_register, 3,
       [{push, [",", 1, r3, "join"]},
	call_method]},

      % return "{" + r3 + "}";
      {push, ["{", r3, "}"]},
      string_add,
      string_add,
      return]}.