Parser/Python.asdl

-- ASDL's four builtin types are identifier, int, string, object

module Python
{
	mod = Module(stmt* body)
	    | Interactive(stmt* body)
	    | Expression(expr body)

	    -- not really an actual node but useful in Jython's typesystem.
	    | Suite(stmt* body)

	stmt = FunctionDef(identifier name, arguments args, 
                           stmt* body, expr* decorator_list, expr? returns)
	      | ClassDef(identifier name, 
			 expr* bases,
			 keyword* keywords,
			 expr? starargs,
			 expr? kwargs,
			 stmt* body,
			 expr* decorator_list)
	      | Return(expr? value)

	      | Delete(expr* targets)
	      | Assign(expr* targets, expr value)
	      | AugAssign(expr target, operator op, expr value)

	      -- use 'orelse' because else is a keyword in target languages
	      | For(expr target, expr iter, stmt* body, stmt* orelse)
	      | While(expr test, stmt* body, stmt* orelse)
	      | If(expr test, stmt* body, stmt* orelse)
	      | With(withitem* items, stmt* body)

	      | Raise(expr? exc, expr? cause)
	      | Try(stmt* body, excepthandler* handlers, stmt* orelse, stmt* finalbody)
	      | Assert(expr test, expr? msg)

	      | Import(alias* names)
	      | ImportFrom(identifier? module, alias* names, int? level)

	      | Global(identifier* names)
	      | Nonlocal(identifier* names)
	      | Expr(expr value)
	      | Pass | Break | Continue

	      -- XXX Jython will be different
	      -- col_offset is the byte offset in the utf8 string the parser uses
	      attributes (int lineno, int col_offset)

	      -- BoolOp() can use left & right?
	expr = BoolOp(boolop op, expr* values)
	     | BinOp(expr left, operator op, expr right)
	     | UnaryOp(unaryop op, expr operand)
	     | Lambda(arguments args, expr body)
	     | IfExp(expr test, expr body, expr orelse)
	     | Dict(expr* keys, expr* values)
	     | Set(expr* elts)
	     | ListComp(expr elt, comprehension* generators)
	     | SetComp(expr elt, comprehension* generators)
	     | DictComp(expr key, expr value, comprehension* generators)
	     | GeneratorExp(expr elt, comprehension* generators)
	     -- the grammar constrains where yield expressions can occur
	     | Yield(expr? value)
	     -- need sequences for compare to distinguish between
	     -- x < 4 < 3 and (x < 4) < 3
	     | Compare(expr left, cmpop* ops, expr* comparators)
	     | Call(expr func, expr* args, keyword* keywords,
			 expr? starargs, expr? kwargs)
	     | Num(object n) -- a number as a PyObject.
	     | Str(string s) -- need to specify raw, unicode, etc?
	     | Bytes(string s)
	     | Ellipsis
	     -- other literals? bools?

	     -- the following expression can appear in assignment context
	     | Attribute(expr value, identifier attr, expr_context ctx)
	     | Subscript(expr value, slice slice, expr_context ctx)
	     | Starred(expr value, expr_context ctx)
	     | Name(identifier id, expr_context ctx)
	     | List(expr* elts, expr_context ctx) 
	     | Tuple(expr* elts, expr_context ctx)

	      -- col_offset is the byte offset in the utf8 string the parser uses
	      attributes (int lineno, int col_offset)

	expr_context = Load | Store | Del | AugLoad | AugStore | Param

	slice = Slice(expr? lower, expr? upper, expr? step) 
	      | ExtSlice(slice* dims) 
	      | Index(expr value) 

	boolop = And | Or 

	operator = Add | Sub | Mult | Div | Mod | Pow | LShift 
                 | RShift | BitOr | BitXor | BitAnd | FloorDiv

	unaryop = Invert | Not | UAdd | USub

	cmpop = Eq | NotEq | Lt | LtE | Gt | GtE | Is | IsNot | In | NotIn

	comprehension = (expr target, expr iter, expr* ifs)

	excepthandler = ExceptHandler(expr? type, identifier? name, stmt* body)
	                attributes (int lineno, int col_offset)

	arguments = (arg* args, identifier? vararg, expr? varargannotation,
                     arg* kwonlyargs, identifier? kwarg,
                     expr? kwargannotation, expr* defaults,
                     expr* kw_defaults)
	arg = (identifier arg, expr? annotation)

        -- keyword arguments supplied to call
        keyword = (identifier arg, expr value)

        -- import name with optional 'as' alias.
        alias = (identifier name, identifier? asname)

        withitem = (expr context_expr, expr? optional_vars)
}