diff --git a/scripts/qapi/expr.py b/scripts/qapi/expr.py
index af802367eff..01cfc13fc3a 100644
--- a/scripts/qapi/expr.py
+++ b/scripts/qapi/expr.py
@@ -34,9 +34,9 @@
 import re
 from typing import (
     Collection,
-    Dict,
     Iterable,
     List,
+    Mapping,
     Optional,
     Union,
     cast,
@@ -44,7 +44,7 @@
 
 from .common import c_name
 from .error import QAPISemError
-from .parser import QAPIDoc
+from .parser import QAPIExpression
 from .source import QAPISourceInfo
 
 
@@ -53,7 +53,7 @@
 # here (and also not practical as long as mypy lacks recursive
 # types), because the purpose of this module is to interrogate that
 # type.
-_JSONObject = Dict[str, object]
+_JSONObject = Mapping[str, object]
 
 
 # See check_name_str(), below.
@@ -229,12 +229,11 @@ def pprint(elems: Iterable[str]) -> str:
                pprint(unknown), pprint(allowed)))
 
 
-def check_flags(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_flags(expr: QAPIExpression) -> None:
     """
     Ensure flag members (if present) have valid values.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError:
         When certain flags have an invalid value, or when
@@ -243,18 +242,18 @@ def check_flags(expr: _JSONObject, info: QAPISourceInfo) -> None:
     for key in ('gen', 'success-response'):
         if key in expr and expr[key] is not False:
             raise QAPISemError(
-                info, "flag '%s' may only use false value" % key)
+                expr.info, "flag '%s' may only use false value" % key)
     for key in ('boxed', 'allow-oob', 'allow-preconfig', 'coroutine'):
         if key in expr and expr[key] is not True:
             raise QAPISemError(
-                info, "flag '%s' may only use true value" % key)
+                expr.info, "flag '%s' may only use true value" % key)
     if 'allow-oob' in expr and 'coroutine' in expr:
         # This is not necessarily a fundamental incompatibility, but
         # we don't have a use case and the desired semantics isn't
         # obvious.  The simplest solution is to forbid it until we get
         # a use case for it.
-        raise QAPISemError(info, "flags 'allow-oob' and 'coroutine' "
-                                 "are incompatible")
+        raise QAPISemError(
+            expr.info, "flags 'allow-oob' and 'coroutine' are incompatible")
 
 
 def check_if(expr: _JSONObject, info: QAPISourceInfo, source: str) -> None:
@@ -447,12 +446,11 @@ def check_features(features: Optional[object],
         check_if(feat, info, source)
 
 
-def check_enum(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_enum(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as an ``enum`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: When ``expr`` is not a valid ``enum``.
     :return: None, ``expr`` is normalized in-place as needed.
@@ -460,6 +458,7 @@ def check_enum(expr: _JSONObject, info: QAPISourceInfo) -> None:
     name = expr['enum']
     members = expr['data']
     prefix = expr.get('prefix')
+    info = expr.info
 
     if not isinstance(members, list):
         raise QAPISemError(info, "'data' must be an array")
@@ -486,12 +485,11 @@ def check_enum(expr: _JSONObject, info: QAPISourceInfo) -> None:
         check_features(member.get('features'), info)
 
 
-def check_struct(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_struct(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as a ``struct`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: When ``expr`` is not a valid ``struct``.
     :return: None, ``expr`` is normalized in-place as needed.
@@ -499,16 +497,15 @@ def check_struct(expr: _JSONObject, info: QAPISourceInfo) -> None:
     name = cast(str, expr['struct'])  # Checked in check_exprs
     members = expr['data']
 
-    check_type(members, info, "'data'", allow_dict=name)
-    check_type(expr.get('base'), info, "'base'")
+    check_type(members, expr.info, "'data'", allow_dict=name)
+    check_type(expr.get('base'), expr.info, "'base'")
 
 
-def check_union(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_union(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as a ``union`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: when ``expr`` is not a valid ``union``.
     :return: None, ``expr`` is normalized in-place as needed.
@@ -517,6 +514,7 @@ def check_union(expr: _JSONObject, info: QAPISourceInfo) -> None:
     base = expr['base']
     discriminator = expr['discriminator']
     members = expr['data']
+    info = expr.info
 
     check_type(base, info, "'base'", allow_dict=name)
     check_name_is_str(discriminator, info, "'discriminator'")
@@ -531,17 +529,17 @@ def check_union(expr: _JSONObject, info: QAPISourceInfo) -> None:
         check_type(value['type'], info, source, allow_array=not base)
 
 
-def check_alternate(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_alternate(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as an ``alternate`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: When ``expr`` is not a valid ``alternate``.
     :return: None, ``expr`` is normalized in-place as needed.
     """
     members = expr['data']
+    info = expr.info
 
     if not members:
         raise QAPISemError(info, "'data' must not be empty")
@@ -557,12 +555,11 @@ def check_alternate(expr: _JSONObject, info: QAPISourceInfo) -> None:
         check_type(value['type'], info, source, allow_array=True)
 
 
-def check_command(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_command(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as a ``command`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: When ``expr`` is not a valid ``command``.
     :return: None, ``expr`` is normalized in-place as needed.
@@ -572,17 +569,16 @@ def check_command(expr: _JSONObject, info: QAPISourceInfo) -> None:
     boxed = expr.get('boxed', False)
 
     if boxed and args is None:
-        raise QAPISemError(info, "'boxed': true requires 'data'")
-    check_type(args, info, "'data'", allow_dict=not boxed)
-    check_type(rets, info, "'returns'", allow_array=True)
+        raise QAPISemError(expr.info, "'boxed': true requires 'data'")
+    check_type(args, expr.info, "'data'", allow_dict=not boxed)
+    check_type(rets, expr.info, "'returns'", allow_array=True)
 
 
-def check_event(expr: _JSONObject, info: QAPISourceInfo) -> None:
+def check_event(expr: QAPIExpression) -> None:
     """
     Normalize and validate this expression as an ``event`` definition.
 
     :param expr: The expression to validate.
-    :param info: QAPI schema source file information.
 
     :raise QAPISemError: When ``expr`` is not a valid ``event``.
     :return: None, ``expr`` is normalized in-place as needed.
@@ -591,37 +587,23 @@ def check_event(expr: _JSONObject, info: QAPISourceInfo) -> None:
     boxed = expr.get('boxed', False)
 
     if boxed and args is None:
-        raise QAPISemError(info, "'boxed': true requires 'data'")
-    check_type(args, info, "'data'", allow_dict=not boxed)
+        raise QAPISemError(expr.info, "'boxed': true requires 'data'")
+    check_type(args, expr.info, "'data'", allow_dict=not boxed)
 
 
-def check_expr(expr_elem: _JSONObject) -> None:
+def check_expr(expr: QAPIExpression) -> None:
     """
     Validate and normalize a parsed QAPI schema expression.
 
-    :param expr_elem: The parsed expression to normalize and validate.
+    :param expr: The parsed expression to normalize and validate.
 
     :raise QAPISemError: When this expression fails validation.
     :return: None, The expression is normalized in-place as needed.
     """
-    # Expression
-    assert isinstance(expr_elem['expr'], dict)
-    for key in expr_elem['expr'].keys():
-        assert isinstance(key, str)
-    expr: _JSONObject = expr_elem['expr']
-
-    # QAPISourceInfo
-    assert isinstance(expr_elem['info'], QAPISourceInfo)
-    info: QAPISourceInfo = expr_elem['info']
-
-    # Optional[QAPIDoc]
-    tmp = expr_elem.get('doc')
-    assert tmp is None or isinstance(tmp, QAPIDoc)
-    doc: Optional[QAPIDoc] = tmp
-
     if 'include' in expr:
         return
 
+    info = expr.info
     metas = set(expr.keys() & {
         'enum', 'struct', 'union', 'alternate', 'command', 'event'})
     if len(metas) != 1:
@@ -637,6 +619,7 @@ def check_expr(expr_elem: _JSONObject) -> None:
     info.set_defn(meta, name)
     check_defn_name_str(name, info, meta)
 
+    doc = expr.doc
     if doc:
         if doc.symbol != name:
             raise QAPISemError(
@@ -649,24 +632,24 @@ def check_expr(expr_elem: _JSONObject) -> None:
     if meta == 'enum':
         check_keys(expr, info, meta,
                    ['enum', 'data'], ['if', 'features', 'prefix'])
-        check_enum(expr, info)
+        check_enum(expr)
     elif meta == 'union':
         check_keys(expr, info, meta,
                    ['union', 'base', 'discriminator', 'data'],
                    ['if', 'features'])
         normalize_members(expr.get('base'))
         normalize_members(expr['data'])
-        check_union(expr, info)
+        check_union(expr)
     elif meta == 'alternate':
         check_keys(expr, info, meta,
                    ['alternate', 'data'], ['if', 'features'])
         normalize_members(expr['data'])
-        check_alternate(expr, info)
+        check_alternate(expr)
     elif meta == 'struct':
         check_keys(expr, info, meta,
                    ['struct', 'data'], ['base', 'if', 'features'])
         normalize_members(expr['data'])
-        check_struct(expr, info)
+        check_struct(expr)
     elif meta == 'command':
         check_keys(expr, info, meta,
                    ['command'],
@@ -674,21 +657,21 @@ def check_expr(expr_elem: _JSONObject) -> None:
                     'gen', 'success-response', 'allow-oob',
                     'allow-preconfig', 'coroutine'])
         normalize_members(expr.get('data'))
-        check_command(expr, info)
+        check_command(expr)
     elif meta == 'event':
         check_keys(expr, info, meta,
                    ['event'], ['data', 'boxed', 'if', 'features'])
         normalize_members(expr.get('data'))
-        check_event(expr, info)
+        check_event(expr)
     else:
         assert False, 'unexpected meta type'
 
     check_if(expr, info, meta)
     check_features(expr.get('features'), info)
-    check_flags(expr, info)
+    check_flags(expr)
 
 
-def check_exprs(exprs: List[_JSONObject]) -> List[_JSONObject]:
+def check_exprs(exprs: List[QAPIExpression]) -> List[QAPIExpression]:
     """
     Validate and normalize a list of parsed QAPI schema expressions.
 
diff --git a/scripts/qapi/parser.py b/scripts/qapi/parser.py
index 1b006cdc133..87b46db7fba 100644
--- a/scripts/qapi/parser.py
+++ b/scripts/qapi/parser.py
@@ -14,13 +14,14 @@
 # This work is licensed under the terms of the GNU GPL, version 2.
 # See the COPYING file in the top-level directory.
 
-from collections import OrderedDict
+from collections import OrderedDict, UserDict
 import os
 import re
 from typing import (
     TYPE_CHECKING,
     Dict,
     List,
+    Mapping,
     Optional,
     Set,
     Union,
@@ -37,15 +38,30 @@
     from .schema import QAPISchemaFeature, QAPISchemaMember
 
 
-#: Represents a single Top Level QAPI schema expression.
-TopLevelExpr = Dict[str, object]
-
 # Return value alias for get_expr().
 _ExprValue = Union[List[object], Dict[str, object], str, bool]
 
-# FIXME: Consolidate and centralize definitions for TopLevelExpr,
-# _ExprValue, _JSONValue, and _JSONObject; currently scattered across
-# several modules.
+
+# FIXME: Consolidate and centralize definitions for _ExprValue,
+# JSONValue, and _JSONObject; currently scattered across several
+# modules.
+
+
+# 3.6 workaround: can be removed when Python 3.7+ is our required version.
+if TYPE_CHECKING:
+    _UserDict = UserDict[str, object]
+else:
+    _UserDict = UserDict
+
+
+class QAPIExpression(_UserDict):
+    def __init__(self,
+                 initialdata: Mapping[str, object],
+                 info: QAPISourceInfo,
+                 doc: Optional['QAPIDoc'] = None):
+        super().__init__(initialdata)
+        self.info = info
+        self.doc: Optional['QAPIDoc'] = doc
 
 
 class QAPIParseError(QAPISourceError):
@@ -100,7 +116,7 @@ def __init__(self,
         self.line_pos = 0
 
         # Parser output:
-        self.exprs: List[Dict[str, object]] = []
+        self.exprs: List[QAPIExpression] = []
         self.docs: List[QAPIDoc] = []
 
         # Showtime!
@@ -147,8 +163,7 @@ def _parse(self) -> None:
                                        "value of 'include' must be a string")
                 incl_fname = os.path.join(os.path.dirname(self._fname),
                                           include)
-                self.exprs.append({'expr': {'include': incl_fname},
-                                   'info': info})
+                self._add_expr(OrderedDict({'include': incl_fname}), info)
                 exprs_include = self._include(include, info, incl_fname,
                                               self._included)
                 if exprs_include:
@@ -165,17 +180,18 @@ def _parse(self) -> None:
                 for name, value in pragma.items():
                     self._pragma(name, value, info)
             else:
-                expr_elem = {'expr': expr,
-                             'info': info}
-                if cur_doc:
-                    if not cur_doc.symbol:
-                        raise QAPISemError(
-                            cur_doc.info, "definition documentation required")
-                    expr_elem['doc'] = cur_doc
-                self.exprs.append(expr_elem)
+                if cur_doc and not cur_doc.symbol:
+                    raise QAPISemError(
+                        cur_doc.info, "definition documentation required")
+                self._add_expr(expr, info, cur_doc)
             cur_doc = None
         self.reject_expr_doc(cur_doc)
 
+    def _add_expr(self, expr: Mapping[str, object],
+                  info: QAPISourceInfo,
+                  doc: Optional['QAPIDoc'] = None) -> None:
+        self.exprs.append(QAPIExpression(expr, info, doc))
+
     @staticmethod
     def reject_expr_doc(doc: Optional['QAPIDoc']) -> None:
         if doc and doc.symbol:
@@ -784,7 +800,7 @@ def connect_feature(self, feature: 'QAPISchemaFeature') -> None:
                                % feature.name)
         self.features[feature.name].connect(feature)
 
-    def check_expr(self, expr: TopLevelExpr) -> None:
+    def check_expr(self, expr: QAPIExpression) -> None:
         if self.has_section('Returns') and 'command' not in expr:
             raise QAPISemError(self.info,
                                "'Returns:' is only valid for commands")
diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
index cd8661125cd..207e4d71f39 100644
--- a/scripts/qapi/schema.py
+++ b/scripts/qapi/schema.py
@@ -17,7 +17,7 @@
 from collections import OrderedDict
 import os
 import re
-from typing import Optional
+from typing import List, Optional
 
 from .common import (
     POINTER_SUFFIX,
@@ -29,7 +29,7 @@
 )
 from .error import QAPIError, QAPISemError, QAPISourceError
 from .expr import check_exprs
-from .parser import QAPISchemaParser
+from .parser import QAPIExpression, QAPISchemaParser
 
 
 class QAPISchemaIfCond:
@@ -964,10 +964,11 @@ def module_by_fname(self, fname):
         name = self._module_name(fname)
         return self._module_dict[name]
 
-    def _def_include(self, expr, info, doc):
+    def _def_include(self, expr: QAPIExpression):
         include = expr['include']
-        assert doc is None
-        self._def_entity(QAPISchemaInclude(self._make_module(include), info))
+        assert expr.doc is None
+        self._def_entity(
+            QAPISchemaInclude(self._make_module(include), expr.info))
 
     def _def_builtin_type(self, name, json_type, c_type):
         self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
@@ -1045,14 +1046,15 @@ def _make_implicit_object_type(self, name, info, ifcond, role, members):
                 name, info, None, ifcond, None, None, members, None))
         return name
 
-    def _def_enum_type(self, expr, info, doc):
+    def _def_enum_type(self, expr: QAPIExpression):
         name = expr['enum']
         data = expr['data']
         prefix = expr.get('prefix')
         ifcond = QAPISchemaIfCond(expr.get('if'))
+        info = expr.info
         features = self._make_features(expr.get('features'), info)
         self._def_entity(QAPISchemaEnumType(
-            name, info, doc, ifcond, features,
+            name, info, expr.doc, ifcond, features,
             self._make_enum_members(data, info), prefix))
 
     def _make_member(self, name, typ, ifcond, features, info):
@@ -1072,14 +1074,15 @@ def _make_members(self, data, info):
                                   value.get('features'), info)
                 for (key, value) in data.items()]
 
-    def _def_struct_type(self, expr, info, doc):
+    def _def_struct_type(self, expr: QAPIExpression):
         name = expr['struct']
         base = expr.get('base')
         data = expr['data']
+        info = expr.info
         ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         self._def_entity(QAPISchemaObjectType(
-            name, info, doc, ifcond, features, base,
+            name, info, expr.doc, ifcond, features, base,
             self._make_members(data, info),
             None))
 
@@ -1089,11 +1092,13 @@ def _make_variant(self, case, typ, ifcond, info):
             typ = self._make_array_type(typ[0], info)
         return QAPISchemaVariant(case, info, typ, ifcond)
 
-    def _def_union_type(self, expr, info, doc):
+    def _def_union_type(self, expr: QAPIExpression):
         name = expr['union']
         base = expr['base']
         tag_name = expr['discriminator']
         data = expr['data']
+        assert isinstance(data, dict)
+        info = expr.info
         ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         if isinstance(base, dict):
@@ -1105,17 +1110,19 @@ def _def_union_type(self, expr, info, doc):
                                QAPISchemaIfCond(value.get('if')),
                                info)
             for (key, value) in data.items()]
-        members = []
+        members: List[QAPISchemaObjectTypeMember] = []
         self._def_entity(
-            QAPISchemaObjectType(name, info, doc, ifcond, features,
+            QAPISchemaObjectType(name, info, expr.doc, ifcond, features,
                                  base, members,
                                  QAPISchemaVariants(
                                      tag_name, info, None, variants)))
 
-    def _def_alternate_type(self, expr, info, doc):
+    def _def_alternate_type(self, expr: QAPIExpression):
         name = expr['alternate']
         data = expr['data']
+        assert isinstance(data, dict)
         ifcond = QAPISchemaIfCond(expr.get('if'))
+        info = expr.info
         features = self._make_features(expr.get('features'), info)
         variants = [
             self._make_variant(key, value['type'],
@@ -1124,11 +1131,11 @@ def _def_alternate_type(self, expr, info, doc):
             for (key, value) in data.items()]
         tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
         self._def_entity(
-            QAPISchemaAlternateType(name, info, doc, ifcond, features,
-                                    QAPISchemaVariants(
-                                        None, info, tag_member, variants)))
+            QAPISchemaAlternateType(
+                name, info, expr.doc, ifcond, features,
+                QAPISchemaVariants(None, info, tag_member, variants)))
 
-    def _def_command(self, expr, info, doc):
+    def _def_command(self, expr: QAPIExpression):
         name = expr['command']
         data = expr.get('data')
         rets = expr.get('returns')
@@ -1139,6 +1146,7 @@ def _def_command(self, expr, info, doc):
         allow_preconfig = expr.get('allow-preconfig', False)
         coroutine = expr.get('coroutine', False)
         ifcond = QAPISchemaIfCond(expr.get('if'))
+        info = expr.info
         features = self._make_features(expr.get('features'), info)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
@@ -1147,44 +1155,42 @@ def _def_command(self, expr, info, doc):
         if isinstance(rets, list):
             assert len(rets) == 1
             rets = self._make_array_type(rets[0], info)
-        self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, features,
-                                           data, rets,
+        self._def_entity(QAPISchemaCommand(name, info, expr.doc, ifcond,
+                                           features, data, rets,
                                            gen, success_response,
                                            boxed, allow_oob, allow_preconfig,
                                            coroutine))
 
-    def _def_event(self, expr, info, doc):
+    def _def_event(self, expr: QAPIExpression):
         name = expr['event']
         data = expr.get('data')
         boxed = expr.get('boxed', False)
         ifcond = QAPISchemaIfCond(expr.get('if'))
+        info = expr.info
         features = self._make_features(expr.get('features'), info)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
                 name, info, ifcond,
                 'arg', self._make_members(data, info))
-        self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, features,
-                                         data, boxed))
+        self._def_entity(QAPISchemaEvent(name, info, expr.doc, ifcond,
+                                         features, data, boxed))
 
     def _def_exprs(self, exprs):
-        for expr_elem in exprs:
-            expr = expr_elem['expr']
-            info = expr_elem['info']
-            doc = expr_elem.get('doc')
+        for expr in exprs:
             if 'enum' in expr:
-                self._def_enum_type(expr, info, doc)
+                self._def_enum_type(expr)
             elif 'struct' in expr:
-                self._def_struct_type(expr, info, doc)
+                self._def_struct_type(expr)
             elif 'union' in expr:
-                self._def_union_type(expr, info, doc)
+                self._def_union_type(expr)
             elif 'alternate' in expr:
-                self._def_alternate_type(expr, info, doc)
+                self._def_alternate_type(expr)
             elif 'command' in expr:
-                self._def_command(expr, info, doc)
+                self._def_command(expr)
             elif 'event' in expr:
-                self._def_event(expr, info, doc)
+                self._def_event(expr)
             elif 'include' in expr:
-                self._def_include(expr, info, doc)
+                self._def_include(expr)
             else:
                 assert False
 
