1 files changed, 1033 insertions, 0 deletions
diff --git a/ipc/ipdl/ipdl/cxx/ast.py b/ipc/ipdl/ipdl/cxx/ast.py
new file mode 100644
index 0000000000..3b9448859b
--- /dev/null
+++ b/ipc/ipdl/ipdl/cxx/ast.py
@@ -0,0 +1,1033 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import copy
+import functools
+
+from ipdl.util import hash_str
+
+
+class Visitor:
+    def defaultVisit(self, node):
+        raise Exception(
+            "INTERNAL ERROR: no visitor for node type `%s'" % (node.__class__.__name__)
+        )
+
+    def visitWhitespace(self, ws):
+        pass
+
+    def visitVerbatimNode(self, verb):
+        pass
+
+    def visitGroupNode(self, group):
+        for node in group.nodes:
+            node.accept(self)
+
+    def visitFile(self, f):
+        for thing in f.stuff:
+            thing.accept(self)
+
+    def visitCppDirective(self, ppd):
+        pass
+
+    def visitBlock(self, block):
+        for stmt in block.stmts:
+            stmt.accept(self)
+
+    def visitNamespace(self, ns):
+        self.visitBlock(ns)
+
+    def visitType(self, type):
+        pass
+
+    def visitTypeArray(self, ta):
+        ta.basetype.accept(self)
+        ta.nmemb.accept(self)
+
+    def visitTypeEnum(self, enum):
+        pass
+
+    def visitTypeFunction(self, fn):
+        pass
+
+    def visitTypeUnion(self, union):
+        for t, name in union.components:
+            t.accept(self)
+
+    def visitTypedef(self, tdef):
+        tdef.fromtype.accept(self)
+
+    def visitUsing(self, us):
+        us.type.accept(self)
+
+    def visitForwardDecl(self, fd):
+        pass
+
+    def visitDecl(self, decl):
+        decl.type.accept(self)
+
+    def visitParam(self, param):
+        self.visitDecl(param)
+        if param.default is not None:
+            param.default.accept(self)
+
+    def visitClass(self, cls):
+        for inherit in cls.inherits:
+            inherit.accept(self)
+        self.visitBlock(cls)
+
+    def visitInherit(self, inh):
+        pass
+
+    def visitFriendClassDecl(self, fcd):
+        pass
+
+    def visitMethodDecl(self, meth):
+        for param in meth.params:
+            param.accept(self)
+        if meth.ret is not None:
+            meth.ret.accept(self)
+        if meth.typeop is not None:
+            meth.typeop.accept(self)
+        if meth.T is not None:
+            meth.T.accept(self)
+
+    def visitMethodDefn(self, meth):
+        meth.decl.accept(self)
+        self.visitBlock(meth)
+
+    def visitFunctionDecl(self, fun):
+        self.visitMethodDecl(fun)
+
+    def visitFunctionDefn(self, fd):
+        self.visitMethodDefn(fd)
+
+    def visitConstructorDecl(self, ctor):
+        self.visitMethodDecl(ctor)
+
+    def visitConstructorDefn(self, cd):
+        cd.decl.accept(self)
+        for init in cd.memberinits:
+            init.accept(self)
+        self.visitBlock(cd)
+
+    def visitDestructorDecl(self, dtor):
+        self.visitMethodDecl(dtor)
+
+    def visitDestructorDefn(self, dd):
+        dd.decl.accept(self)
+        self.visitBlock(dd)
+
+    def visitExprLiteral(self, l):
+        pass
+
+    def visitExprVar(self, v):
+        pass
+
+    def visitExprPrefixUnop(self, e):
+        e.expr.accept(self)
+
+    def visitExprBinary(self, e):
+        e.left.accept(self)
+        e.right.accept(self)
+
+    def visitExprConditional(self, c):
+        c.cond.accept(self)
+        c.ife.accept(self)
+        c.elsee.accept(self)
+
+    def visitExprAddrOf(self, eao):
+        self.visitExprPrefixUnop(eao)
+
+    def visitExprDeref(self, ed):
+        self.visitExprPrefixUnop(ed)
+
+    def visitExprNot(self, en):
+        self.visitExprPrefixUnop(en)
+
+    def visitExprCast(self, ec):
+        ec.expr.accept(self)
+
+    def visitExprSelect(self, es):
+        es.obj.accept(self)
+
+    def visitExprAssn(self, ea):
+        ea.lhs.accept(self)
+        ea.rhs.accept(self)
+
+    def visitExprCall(self, ec):
+        ec.func.accept(self)
+        for arg in ec.args:
+            arg.accept(self)
+
+    def visitExprMove(self, ec):
+        self.visitExprCall(ec)
+
+    def visitExprNothing(self, ec):
+        self.visitExprCall(ec)
+
+    def visitExprSome(self, ec):
+        self.visitExprCall(ec)
+
+    def visitExprNew(self, en):
+        en.ctype.accept(self)
+        if en.newargs is not None:
+            for arg in en.newargs:
+                arg.accept(self)
+        if en.args is not None:
+            for arg in en.args:
+                arg.accept(self)
+
+    def visitExprDelete(self, ed):
+        ed.obj.accept(self)
+
+    def visitExprMemberInit(self, minit):
+        self.visitExprCall(minit)
+
+    def visitExprLambda(self, l):
+        self.visitBlock(l)
+
+    def visitStmtBlock(self, sb):
+        self.visitBlock(sb)
+
+    def visitStmtDecl(self, sd):
+        sd.decl.accept(self)
+        if sd.init is not None:
+            sd.init.accept(self)
+
+    def visitLabel(self, label):
+        pass
+
+    def visitCaseLabel(self, case):
+        pass
+
+    def visitDefaultLabel(self, dl):
+        pass
+
+    def visitStmtIf(self, si):
+        si.cond.accept(self)
+        si.ifb.accept(self)
+        if si.elseb is not None:
+            si.elseb.accept(self)
+
+    def visitStmtFor(self, sf):
+        if sf.init is not None:
+            sf.init.accept(self)
+        if sf.cond is not None:
+            sf.cond.accept(self)
+        if sf.update is not None:
+            sf.update.accept(self)
+
+    def visitStmtSwitch(self, ss):
+        ss.expr.accept(self)
+        self.visitBlock(ss)
+
+    def visitStmtBreak(self, sb):
+        pass
+
+    def visitStmtExpr(self, se):
+        se.expr.accept(self)
+
+    def visitStmtReturn(self, sr):
+        if sr.expr is not None:
+            sr.expr.accept(self)
+
+
+# ------------------------------
+
+
+class Node:
+    def __init__(self):
+        pass
+
+    def accept(self, visitor):
+        visit = getattr(visitor, "visit" + self.__class__.__name__, None)
+        if visit is None:
+            return getattr(visitor, "defaultVisit")(self)
+        return visit(self)
+
+
+class Whitespace(Node):
+    # yes, this is silly.  but we need to stick comments in the
+    # generated code without resorting to more serious hacks
+    def __init__(self, ws, indent=False):
+        Node.__init__(self)
+        self.ws = ws
+        self.indent = indent
+
+
+Whitespace.NL = Whitespace("\n")
+
+
+class VerbatimNode(Node):
+    # A block of text to be written verbatim to the output file.
+    #
+    # NOTE: This node is usually created by `code`. See `code.py` for details.
+    # FIXME: Merge Whitespace and VerbatimNode? They're identical.
+    def __init__(self, text, indent=0):
+        Node.__init__(self)
+        self.text = text
+        self.indent = indent
+
+
+class GroupNode(Node):
+    # A group of nodes to be treated as a single node. These nodes have an
+    # optional indentation level which should be applied when generating them.
+    #
+    # NOTE: This node is usually created by `code`. See `code.py` for details.
+    def __init__(self, nodes, offset=0):
+        Node.__init__(self)
+        self.nodes = nodes
+        self.offset = offset
+
+
+class File(Node):
+    def __init__(self, filename):
+        Node.__init__(self)
+        self.name = filename
+        # array of stuff in the file --- stmts and preprocessor thingies
+        self.stuff = []
+
+    def addthing(self, thing):
+        assert thing is not None
+        assert not isinstance(thing, list)
+        self.stuff.append(thing)
+
+    def addthings(self, things):
+        for t in things:
+            self.addthing(t)
+
+    # "look like" a Block so code doesn't have to care whether they're
+    # in global scope or not
+    def addstmt(self, stmt):
+        assert stmt is not None
+        assert not isinstance(stmt, list)
+        self.stuff.append(stmt)
+
+    def addstmts(self, stmts):
+        for s in stmts:
+            self.addstmt(s)
+
+    def addcode(self, tmpl, **context):
+        from ipdl.cxx.code import StmtCode
+
+        self.addstmt(StmtCode(tmpl, **context))
+
+
+class CppDirective(Node):
+    """represents |#[directive] [rest]|, where |rest| is any string"""
+
+    def __init__(self, directive, rest=None):
+        Node.__init__(self)
+        self.directive = directive
+        self.rest = rest
+
+
+class Block(Node):
+    def __init__(self):
+        Node.__init__(self)
+        self.stmts = []
+
+    def addstmt(self, stmt):
+        assert stmt is not None
+        assert not isinstance(stmt, tuple)
+        self.stmts.append(stmt)
+
+    def addstmts(self, stmts):
+        for s in stmts:
+            self.addstmt(s)
+
+    def addcode(self, tmpl, **context):
+        from ipdl.cxx.code import StmtCode
+
+        self.addstmt(StmtCode(tmpl, **context))
+
+
+# ------------------------------
+# type and decl thingies
+
+
+class Namespace(Block):
+    def __init__(self, name):
+        assert isinstance(name, str)
+
+        Block.__init__(self)
+        self.name = name
+
+
+class Type(Node):
+    def __init__(
+        self,
+        name,
+        const=False,
+        ptr=False,
+        ptrptr=False,
+        ptrconstptr=False,
+        ref=False,
+        rvalref=False,
+        rightconst=False,
+        hasimplicitcopyctor=True,
+        T=None,
+        inner=None,
+    ):
+        """
+        Represents the type |name<T>::inner| with the ptr and const
+        modifiers as specified.
+
+        To avoid getting fancy with recursive types, we limit the kinds
+        of pointer types that can be be constructed.
+
+          ptr            => T*
+          ptrptr         => T**
+          ptrconstptr    => T* const*
+          ref            => T&
+          rvalref        => T&&
+
+        Any type, naked or pointer, can be const (const T) or ref (T&)."""
+        # XXX(nika): This type is complex enough at this point, perhaps we
+        # should get "fancy with recursive types" to simplify it.
+        assert isinstance(name, str)
+        assert isinstance(const, bool)
+        assert isinstance(ptr, bool)
+        assert isinstance(ptrptr, bool)
+        assert isinstance(ptrconstptr, bool)
+        assert isinstance(ref, bool)
+        assert isinstance(rvalref, bool)
+        assert isinstance(rightconst, bool)
+        assert not isinstance(T, str)
+
+        Node.__init__(self)
+        self.name = name
+        self.const = const
+        self.ptr = ptr
+        self.ptrptr = ptrptr
+        self.ptrconstptr = ptrconstptr
+        self.ref = ref
+        self.rvalref = rvalref
+        self.rightconst = rightconst
+        self.hasimplicitcopyctor = hasimplicitcopyctor
+        self.T = T
+        self.inner = inner
+        # XXX could get serious here with recursive types, but shouldn't
+        # need that for this codegen
+
+    def __deepcopy__(self, memo):
+        return Type(
+            self.name,
+            const=self.const,
+            ptr=self.ptr,
+            ptrptr=self.ptrptr,
+            ptrconstptr=self.ptrconstptr,
+            ref=self.ref,
+            rvalref=self.rvalref,
+            rightconst=self.rightconst,
+            T=copy.deepcopy(self.T, memo),
+            inner=copy.deepcopy(self.inner, memo),
+        )
+
+
+Type.BOOL = Type("bool")
+Type.INT = Type("int")
+Type.INT32 = Type("int32_t")
+Type.INTPTR = Type("intptr_t")
+Type.NSRESULT = Type("nsresult")
+Type.UINT32 = Type("uint32_t")
+Type.UINT32PTR = Type("uint32_t", ptr=True)
+Type.SIZE = Type("size_t")
+Type.VOID = Type("void")
+Type.VOIDPTR = Type("void", ptr=True)
+Type.AUTO = Type("auto")
+Type.AUTORVAL = Type("auto", rvalref=True)
+
+
+class TypeArray(Node):
+    def __init__(self, basetype, nmemb):
+        """the type |basetype DECLNAME[nmemb]|.  |nmemb| is an Expr"""
+        self.basetype = basetype
+        self.nmemb = nmemb
+
+
+class TypeEnum(Node):
+    def __init__(self, name=None):
+        """name can be None"""
+        Node.__init__(self)
+        self.name = name
+        self.idnums = []  # pairs of ('Foo', [num]) or ('Foo', None)
+
+    def addId(self, id, num=None):
+        self.idnums.append((id, num))
+
+
+class TypeUnion(Node):
+    def __init__(self, name=None):
+        Node.__init__(self)
+        self.name = name
+        self.components = []  # [ Decl ]
+
+    def addComponent(self, type, name):
+        self.components.append(Decl(type, name))
+
+
+class TypeFunction(Node):
+    def __init__(self, params=[], ret=Type("void")):
+        """Anonymous function type std::function<>"""
+        self.params = params
+        self.ret = ret
+
+
+@functools.total_ordering
+class Typedef(Node):
+    def __init__(self, fromtype, totypename, templateargs=[]):
+        assert isinstance(totypename, str)
+
+        Node.__init__(self)
+        self.fromtype = fromtype
+        self.totypename = totypename
+        self.templateargs = templateargs
+
+    def __lt__(self, other):
+        return self.totypename < other.totypename
+
+    def __eq__(self, other):
+        return self.__class__ == other.__class__ and self.totypename == other.totypename
+
+    def __hash__(self):
+        return hash_str(self.totypename)
+
+
+class Using(Node):
+    def __init__(self, type):
+        Node.__init__(self)
+        self.type = type
+
+
+class ForwardDecl(Node):
+    def __init__(self, pqname, cls=False, struct=False):
+        # Exactly one of cls and struct must be set
+        assert cls ^ struct
+
+        self.pqname = pqname
+        self.cls = cls
+        self.struct = struct
+
+
+class Decl(Node):
+    """represents |Foo bar|, e.g. in a function signature"""
+
+    def __init__(self, type, name):
+        assert type is not None
+        assert not isinstance(type, str)
+        assert isinstance(name, str)
+
+        Node.__init__(self)
+        self.type = type
+        self.name = name
+
+    def __deepcopy__(self, memo):
+        return Decl(copy.deepcopy(self.type, memo), self.name)
+
+
+class Param(Decl):
+    def __init__(self, type, name, default=None):
+        Decl.__init__(self, type, name)
+        self.default = default
+
+    def __deepcopy__(self, memo):
+        return Param(
+            copy.deepcopy(self.type, memo), self.name, copy.deepcopy(self.default, memo)
+        )
+
+
+# ------------------------------
+# class stuff
+
+
+class Class(Block):
+    def __init__(
+        self,
+        name,
+        inherits=[],
+        interface=False,
+        abstract=False,
+        final=False,
+        specializes=None,
+        struct=False,
+    ):
+        assert not (interface and abstract)
+        assert not (abstract and final)
+        assert not (interface and final)
+        assert not (inherits and specializes)
+
+        Block.__init__(self)
+        self.name = name
+        self.inherits = inherits  # [ Type ]
+        self.interface = interface  # bool
+        self.abstract = abstract  # bool
+        self.final = final  # bool
+        self.specializes = specializes  # Type or None
+        self.struct = struct  # bool
+
+
+class Inherit(Node):
+    def __init__(self, type, viz="public"):
+        assert isinstance(viz, str)
+        Node.__init__(self)
+        self.type = type
+        self.viz = viz
+
+
+class FriendClassDecl(Node):
+    def __init__(self, friend):
+        Node.__init__(self)
+        self.friend = friend
+
+
+# Python2 polyfill for Python3's Enum() functional API.
+
+
+def make_enum(name, members_str):
+    members_list = members_str.split()
+    members_dict = {}
+    for member_value, member in enumerate(members_list, start=1):
+        members_dict[member] = member_value
+    return type(name, (), members_dict)
+
+
+MethodSpec = make_enum("MethodSpec", "NONE VIRTUAL PURE OVERRIDE STATIC")
+
+
+class MethodDecl(Node):
+    def __init__(
+        self,
+        name,
+        params=[],
+        ret=Type("void"),
+        methodspec=MethodSpec.NONE,
+        const=False,
+        warn_unused=False,
+        force_inline=False,
+        typeop=None,
+        T=None,
+        cls=None,
+    ):
+        assert not (name and typeop)
+        assert name is None or isinstance(name, str)
+        assert not isinstance(ret, list)
+        for decl in params:
+            assert not isinstance(decl, str)
+        assert not isinstance(T, int)
+        assert isinstance(const, bool)
+        assert isinstance(warn_unused, bool)
+        assert isinstance(force_inline, bool)
+
+        if typeop is not None:
+            assert methodspec == MethodSpec.NONE
+            ret = None
+
+        Node.__init__(self)
+        self.name = name
+        self.params = params  # [ Param ]
+        self.ret = ret  # Type or None
+        self.methodspec = methodspec  # enum
+        self.const = const  # bool
+        self.warn_unused = warn_unused  # bool
+        self.force_inline = force_inline or bool(T)  # bool
+        self.typeop = typeop  # Type or None
+        self.T = T  # Type or None
+        self.cls = cls  # Class or None
+        self.only_for_definition = False
+
+    def __deepcopy__(self, memo):
+        return MethodDecl(
+            self.name,
+            params=copy.deepcopy(self.params, memo),
+            ret=copy.deepcopy(self.ret, memo),
+            methodspec=self.methodspec,
+            const=self.const,
+            warn_unused=self.warn_unused,
+            force_inline=self.force_inline,
+            typeop=copy.deepcopy(self.typeop, memo),
+            T=copy.deepcopy(self.T, memo),
+        )
+
+
+class MethodDefn(Block):
+    def __init__(self, decl):
+        Block.__init__(self)
+        self.decl = decl
+
+
+class FunctionDecl(MethodDecl):
+    def __init__(
+        self,
+        name,
+        params=[],
+        ret=Type("void"),
+        methodspec=MethodSpec.NONE,
+        warn_unused=False,
+        force_inline=False,
+        T=None,
+    ):
+        assert methodspec == MethodSpec.NONE or methodspec == MethodSpec.STATIC
+        MethodDecl.__init__(
+            self,
+            name,
+            params=params,
+            ret=ret,
+            methodspec=methodspec,
+            warn_unused=warn_unused,
+            force_inline=force_inline,
+            T=T,
+        )
+
+
+class FunctionDefn(MethodDefn):
+    def __init__(self, decl):
+        MethodDefn.__init__(self, decl)
+
+
+class ConstructorDecl(MethodDecl):
+    def __init__(self, name, params=[], explicit=False, force_inline=False):
+        MethodDecl.__init__(
+            self, name, params=params, ret=None, force_inline=force_inline
+        )
+        self.explicit = explicit
+
+    def __deepcopy__(self, memo):
+        return ConstructorDecl(
+            self.name, copy.deepcopy(self.params, memo), self.explicit
+        )
+
+
+class ConstructorDefn(MethodDefn):
+    def __init__(self, decl, memberinits=[]):
+        MethodDefn.__init__(self, decl)
+        self.memberinits = memberinits
+
+
+class DestructorDecl(MethodDecl):
+    def __init__(self, name, methodspec=MethodSpec.NONE, force_inline=False):
+        # C++ allows pure or override destructors, but ipdl cgen does not.
+        assert methodspec == MethodSpec.NONE or methodspec == MethodSpec.VIRTUAL
+        MethodDecl.__init__(
+            self,
+            name,
+            params=[],
+            ret=None,
+            methodspec=methodspec,
+            force_inline=force_inline,
+        )
+
+    def __deepcopy__(self, memo):
+        return DestructorDecl(
+            self.name, methodspec=self.methodspec, force_inline=self.force_inline
+        )
+
+
+class DestructorDefn(MethodDefn):
+    def __init__(self, decl):
+        MethodDefn.__init__(self, decl)
+
+
+# ------------------------------
+# expressions
+
+
+class ExprVar(Node):
+    def __init__(self, name):
+        assert isinstance(name, str)
+
+        Node.__init__(self)
+        self.name = name
+
+
+ExprVar.THIS = ExprVar("this")
+
+
+class ExprLiteral(Node):
+    def __init__(self, value, type):
+        """|type| is a Python format specifier; 'd' for example"""
+        Node.__init__(self)
+        self.value = value
+        self.type = type
+
+    @staticmethod
+    def Int(i):
+        return ExprLiteral(i, "d")
+
+    @staticmethod
+    def String(s):
+        return ExprLiteral('"' + s + '"', "s")
+
+    def __str__(self):
+        return ("%" + self.type) % (self.value)
+
+
+ExprLiteral.ZERO = ExprLiteral.Int(0)
+ExprLiteral.ONE = ExprLiteral.Int(1)
+ExprLiteral.NULL = ExprVar("nullptr")
+ExprLiteral.TRUE = ExprVar("true")
+ExprLiteral.FALSE = ExprVar("false")
+
+
+class ExprPrefixUnop(Node):
+    def __init__(self, expr, op):
+        assert not isinstance(expr, tuple)
+        self.expr = expr
+        self.op = op
+
+
+class ExprNot(ExprPrefixUnop):
+    def __init__(self, expr):
+        ExprPrefixUnop.__init__(self, expr, "!")
+
+
+class ExprAddrOf(ExprPrefixUnop):
+    def __init__(self, expr):
+        ExprPrefixUnop.__init__(self, expr, "&")
+
+
+class ExprDeref(ExprPrefixUnop):
+    def __init__(self, expr):
+        ExprPrefixUnop.__init__(self, expr, "*")
+
+
+class ExprCast(Node):
+    def __init__(self, expr, type, static=False, const=False):
+        # Exactly one of these should be set
+        assert static ^ const
+
+        Node.__init__(self)
+        self.expr = expr
+        self.type = type
+        self.static = static
+        self.const = const
+
+
+class ExprBinary(Node):
+    def __init__(self, left, op, right):
+        Node.__init__(self)
+        self.left = left
+        self.op = op
+        self.right = right
+
+
+class ExprConditional(Node):
+    def __init__(self, cond, ife, elsee):
+        Node.__init__(self)
+        self.cond = cond
+        self.ife = ife
+        self.elsee = elsee
+
+
+class ExprSelect(Node):
+    def __init__(self, obj, op, field):
+        assert obj and op and field
+        assert not isinstance(obj, str)
+        assert isinstance(op, str)
+
+        Node.__init__(self)
+        self.obj = obj
+        self.op = op
+        if isinstance(field, str):
+            self.field = ExprVar(field)
+        else:
+            self.field = field
+
+
+class ExprAssn(Node):
+    def __init__(self, lhs, rhs, op="="):
+        Node.__init__(self)
+        self.lhs = lhs
+        self.op = op
+        self.rhs = rhs
+
+
+class ExprCall(Node):
+    def __init__(self, func, args=[]):
+        assert hasattr(func, "accept")
+        assert isinstance(args, list)
+        for arg in args:
+            assert arg and not isinstance(arg, str)
+
+        Node.__init__(self)
+        self.func = func
+        self.args = args
+
+
+class ExprMove(ExprCall):
+    def __init__(self, arg):
+        ExprCall.__init__(self, ExprVar("std::move"), args=[arg])
+
+
+class ExprNew(Node):
+    # XXX taking some poetic license ...
+    def __init__(self, ctype, args=[], newargs=None):
+        assert not (ctype.const or ctype.ref or ctype.rvalref)
+
+        Node.__init__(self)
+        self.ctype = ctype
+        self.args = args
+        self.newargs = newargs
+
+
+class ExprDelete(Node):
+    def __init__(self, obj):
+        Node.__init__(self)
+        self.obj = obj
+
+
+class ExprMemberInit(ExprCall):
+    def __init__(self, member, args=[]):
+        ExprCall.__init__(self, member, args)
+
+
+class ExprLambda(Block):
+    def __init__(self, captures=[], params=[], ret=None):
+        Block.__init__(self)
+        assert isinstance(captures, list)
+        assert isinstance(params, list)
+        self.captures = captures
+        self.params = params
+        self.ret = ret
+
+
+# ------------------------------
+# statements etc.
+
+
+class StmtBlock(Block):
+    def __init__(self, stmts=[]):
+        Block.__init__(self)
+        self.addstmts(stmts)
+
+
+class StmtDecl(Node):
+    def __init__(self, decl, init=None, initargs=None):
+        assert not (init and initargs)
+        assert not isinstance(init, str)  # easy to confuse with Decl
+        assert not isinstance(init, list)
+        assert not isinstance(decl, tuple)
+
+        Node.__init__(self)
+        self.decl = decl
+        self.init = init
+        self.initargs = initargs
+
+
+class Label(Node):
+    def __init__(self, name):
+        Node.__init__(self)
+        self.name = name
+
+
+Label.PUBLIC = Label("public")
+Label.PROTECTED = Label("protected")
+Label.PRIVATE = Label("private")
+
+
+class CaseLabel(Node):
+    def __init__(self, name):
+        Node.__init__(self)
+        self.name = name
+
+
+class DefaultLabel(Node):
+    def __init__(self):
+        Node.__init__(self)
+
+
+class StmtIf(Node):
+    def __init__(self, cond):
+        Node.__init__(self)
+        self.cond = cond
+        self.ifb = Block()
+        self.elseb = None
+
+    def addifstmt(self, stmt):
+        self.ifb.addstmt(stmt)
+
+    def addifstmts(self, stmts):
+        self.ifb.addstmts(stmts)
+
+    def addelsestmt(self, stmt):
+        if self.elseb is None:
+            self.elseb = Block()
+        self.elseb.addstmt(stmt)
+
+    def addelsestmts(self, stmts):
+        if self.elseb is None:
+            self.elseb = Block()
+        self.elseb.addstmts(stmts)
+
+
+class StmtFor(Block):
+    def __init__(self, init=None, cond=None, update=None):
+        Block.__init__(self)
+        self.init = init
+        self.cond = cond
+        self.update = update
+
+
+class StmtRangedFor(Block):
+    def __init__(self, var, iteree):
+        assert isinstance(var, ExprVar)
+        assert iteree
+
+        Block.__init__(self)
+        self.var = var
+        self.iteree = iteree
+
+
+class StmtSwitch(Block):
+    def __init__(self, expr):
+        Block.__init__(self)
+        self.expr = expr
+        self.nr_cases = 0
+
+    def addcase(self, case, block):
+        """NOTE: |case| is not checked for uniqueness"""
+        assert not isinstance(case, str)
+        assert (
+            isinstance(block, StmtBreak)
+            or isinstance(block, StmtReturn)
+            or isinstance(block, StmtSwitch)
+            or isinstance(block, GroupNode)
+            or isinstance(block, VerbatimNode)
+            or (
+                hasattr(block, "stmts")
+                and (
+                    isinstance(block.stmts[-1], StmtBreak)
+                    or isinstance(block.stmts[-1], StmtReturn)
+                    or isinstance(block.stmts[-1], GroupNode)
+                    or isinstance(block.stmts[-1], VerbatimNode)
+                )
+            )
+        )
+        self.addstmt(case)
+        self.addstmt(block)
+        self.nr_cases += 1
+
+
+class StmtBreak(Node):
+    def __init__(self):
+        Node.__init__(self)
+
+
+class StmtExpr(Node):
+    def __init__(self, expr):
+        assert expr is not None
+
+        Node.__init__(self)
+        self.expr = expr
+
+
+class StmtReturn(Node):
+    def __init__(self, expr=None):
+        Node.__init__(self)
+        self.expr = expr
+
+
+StmtReturn.TRUE = StmtReturn(ExprLiteral.TRUE)
+StmtReturn.FALSE = StmtReturn(ExprLiteral.FALSE)