From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Fri, 3 Nov 2023 18:48:52 +0000 (-0400)
Subject: cpp-common/bt2: add and use `bt2::internal::Dep*` type alias templates
X-Git-Url: http://git.efficios.com/?p=babeltrace.git;a=commitdiff_plain;h=8047a1755063eb23e5a07b3b96441e50c366ea87

cpp-common/bt2: add and use `bt2::internal::Dep*` type alias templates

Those new templates take care of using `std::conditional` instead of
having to use it at each site. The template parameters of
`bt2::internal::DepType` are:

1. What to check for constness.
2. The effective type if `LibObjT` is NOT `const`.
3. The effective type if `LibObjT` is `const`.

Other `bt2::internal::Dep*` reuse `DepType` with specific types for
parameters 2 and 3 for common uses.

For example:

    using UserAttributes =
        typename std::conditional<std::is_const<LibObjT>::value,
                                  ConstMapValue,
                                  MapValue>::type;

gets replaced by:

    using UserAttributes = internal::DepUserAttrs<LibObjT>;

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Change-Id: I434b9ae82d170c6fe8359488e78c0e3e34a064cd
Reviewed-on: https://review.lttng.org/c/babeltrace/+/11234
Reviewed-by: Simon Marchi <simon.marchi@efficios.com>
---

diff --git a/src/cpp-common/bt2/clock-class.hpp b/src/cpp-common/bt2/clock-class.hpp
index 589526ed..48ff132e 100644
--- a/src/cpp-common/bt2/clock-class.hpp
+++ b/src/cpp-common/bt2/clock-class.hpp
@@ -101,8 +101,7 @@ private:
 public:
     using Shared = SharedObject<_ThisCommonClockClass, LibObjT, internal::ClockClassRefFuncs>;
 
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonClockClass(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {
diff --git a/src/cpp-common/bt2/field-class.hpp b/src/cpp-common/bt2/field-class.hpp
index 461321fb..a053da3d 100644
--- a/src/cpp-common/bt2/field-class.hpp
+++ b/src/cpp-common/bt2/field-class.hpp
@@ -172,9 +172,7 @@ protected:
 
 public:
     using Shared = SharedFieldClass<CommonFieldClass<LibObjT>, LibObjT>;
-
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonFieldClass(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {
@@ -998,13 +996,10 @@ class CommonStructureFieldClassMember final : public BorrowedObject<LibObjT>
 private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using typename BorrowedObject<LibObjT>::_ThisBorrowedObject;
-
-    using _FieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstFieldClass, FieldClass>::type;
+    using _FieldClass = internal::DepFc<LibObjT>;
 
 public:
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonStructureFieldClassMember(const _LibObjPtr libObjPtr) noexcept :
         _ThisBorrowedObject {libObjPtr}
@@ -1131,9 +1126,9 @@ private:
 
 public:
     using Shared = SharedFieldClass<CommonStructureFieldClass<LibObjT>, LibObjT>;
+
     using Member =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstStructureFieldClassMember,
-                                  StructureFieldClassMember>::type;
+        internal::DepType<LibObjT, StructureFieldClassMember, ConstStructureFieldClassMember>;
 
     using Iterator = CommonIterator<CommonStructureFieldClass<LibObjT>, Member>;
 
@@ -1274,9 +1269,7 @@ class CommonArrayFieldClass : public CommonFieldClass<LibObjT>
 {
 private:
     using typename CommonFieldClass<LibObjT>::_ThisCommonFieldClass;
-
-    using _FieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstFieldClass, FieldClass>::type;
+    using _FieldClass = internal::DepFc<LibObjT>;
 
 protected:
     using typename CommonFieldClass<LibObjT>::_LibObjPtr;
@@ -1517,9 +1510,7 @@ class CommonOptionFieldClass : public CommonFieldClass<LibObjT>
 {
 private:
     using typename CommonFieldClass<LibObjT>::_ThisCommonFieldClass;
-
-    using _FieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstFieldClass, FieldClass>::type;
+    using _FieldClass = internal::DepFc<LibObjT>;
 
 protected:
     using typename CommonFieldClass<LibObjT>::_LibObjPtr;
@@ -1909,13 +1900,10 @@ class CommonVariantFieldClassOption : public BorrowedObject<LibObjT>
 private:
     using typename BorrowedObject<LibObjT>::_ThisBorrowedObject;
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
-
-    using _FieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstFieldClass, FieldClass>::type;
+    using _FieldClass = internal::DepFc<LibObjT>;
 
 public:
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonVariantFieldClassOption(const _LibObjPtr libObjPtr) noexcept :
         _ThisBorrowedObject {libObjPtr}
@@ -2167,8 +2155,7 @@ public:
     using Shared = SharedFieldClass<CommonVariantFieldClass<LibObjT>, LibObjT>;
 
     using Option =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstVariantFieldClassOption,
-                                  VariantFieldClassOption>::type;
+        internal::DepType<LibObjT, VariantFieldClassOption, ConstVariantFieldClassOption>;
 
     using Iterator = CommonIterator<CommonVariantFieldClass, Option>;
 
diff --git a/src/cpp-common/bt2/field.hpp b/src/cpp-common/bt2/field.hpp
index 187d6a57..aa160289 100644
--- a/src/cpp-common/bt2/field.hpp
+++ b/src/cpp-common/bt2/field.hpp
@@ -102,8 +102,7 @@ protected:
     using _ThisCommonField = CommonField<LibObjT>;
 
 public:
-    using Class =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstFieldClass, FieldClass>::type;
+    using Class = internal::DepFc<LibObjT>;
 
     explicit CommonField(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {
@@ -333,8 +332,7 @@ private:
     using typename CommonField<LibObjT>::_ThisCommonField;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstBitArrayFieldClass,
-                                            BitArrayFieldClass>::type;
+    using Class = internal::DepType<LibObjT, BitArrayFieldClass, ConstBitArrayFieldClass>;
 
     explicit CommonBitArrayField(const _LibObjPtr libObjPtr) noexcept : _ThisCommonField {libObjPtr}
     {
@@ -426,9 +424,7 @@ protected:
 
 public:
     using Value = std::uint64_t;
-
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstIntegerFieldClass,
-                                            IntegerFieldClass>::type;
+    using Class = internal::DepType<LibObjT, IntegerFieldClass, ConstIntegerFieldClass>;
 
     explicit CommonUnsignedIntegerField(const _LibObjPtr libObjPtr) noexcept :
         _ThisCommonField {libObjPtr}
@@ -515,9 +511,7 @@ protected:
 
 public:
     using Value = std::int64_t;
-
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstIntegerFieldClass,
-                                            IntegerFieldClass>::type;
+    using Class = internal::DepType<LibObjT, IntegerFieldClass, ConstIntegerFieldClass>;
 
     explicit CommonSignedIntegerField(const _LibObjPtr libObjPtr) noexcept :
         _ThisCommonField {libObjPtr}
@@ -631,9 +625,8 @@ private:
     using typename CommonField<LibObjT>::_LibObjPtr;
 
 public:
-    using Class =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstUnsignedEnumerationFieldClass,
-                                  UnsignedEnumerationFieldClass>::type;
+    using Class = internal::DepType<LibObjT, UnsignedEnumerationFieldClass,
+                                    ConstUnsignedEnumerationFieldClass>;
 
     explicit CommonUnsignedEnumerationField(const _LibObjPtr libObjPtr) noexcept :
         _ThisCommonUnsignedIntegerField {libObjPtr}
@@ -715,8 +708,7 @@ private:
 
 public:
     using Class =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstSignedEnumerationFieldClass,
-                                  SignedEnumerationFieldClass>::type;
+        internal::DepType<LibObjT, SignedEnumerationFieldClass, ConstSignedEnumerationFieldClass>;
 
     explicit CommonSignedEnumerationField(const _LibObjPtr libObjPtr) noexcept :
         _ThisCommonSignedIntegerField {libObjPtr}
@@ -1094,8 +1086,7 @@ private:
     using _Spec = internal::CommonStructureFieldSpec<LibObjT>;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstStructureFieldClass,
-                                            StructureFieldClass>::type;
+    using Class = internal::DepType<LibObjT, StructureFieldClass, ConstStructureFieldClass>;
 
     explicit CommonStructureField(const _LibObjPtr libObjPtr) noexcept :
         _ThisCommonField {libObjPtr}
@@ -1213,8 +1204,7 @@ protected:
     using _ThisCommonArrayField = CommonArrayField<LibObjT>;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstArrayFieldClass,
-                                            ArrayFieldClass>::type;
+    using Class = internal::DepType<LibObjT, ArrayFieldClass, ConstArrayFieldClass>;
 
     explicit CommonArrayField(const _LibObjPtr libObjPtr) noexcept : _ThisCommonField {libObjPtr}
     {
@@ -1383,8 +1373,7 @@ private:
     using _Spec = internal::CommonOptionFieldSpec<LibObjT>;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstOptionFieldClass,
-                                            OptionFieldClass>::type;
+    using Class = internal::DepType<LibObjT, OptionFieldClass, ConstOptionFieldClass>;
 
     explicit CommonOptionField(const _LibObjPtr libObjPtr) noexcept : _ThisCommonField {libObjPtr}
     {
@@ -1493,8 +1482,7 @@ private:
     using _Spec = internal::CommonVariantFieldSpec<LibObjT>;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value, ConstVariantFieldClass,
-                                            VariantFieldClass>::type;
+    using Class = internal::DepType<LibObjT, VariantFieldClass, ConstVariantFieldClass>;
 
     explicit CommonVariantField(const _LibObjPtr libObjPtr) noexcept : _ThisCommonField {libObjPtr}
     {
diff --git a/src/cpp-common/bt2/internal/utils.hpp b/src/cpp-common/bt2/internal/utils.hpp
index 3c655b88..4ec736fd 100644
--- a/src/cpp-common/bt2/internal/utils.hpp
+++ b/src/cpp-common/bt2/internal/utils.hpp
@@ -7,9 +7,26 @@
 #ifndef BABELTRACE_CPP_COMMON_BT2_INTERNAL_UTILS_HPP
 #define BABELTRACE_CPP_COMMON_BT2_INTERNAL_UTILS_HPP
 
+#include <type_traits>
+
+#include <babeltrace2/babeltrace.h>
+
 #include "../exc.hpp"
 
 namespace bt2 {
+
+template <typename>
+class CommonMapValue;
+
+template <typename>
+class CommonFieldClass;
+
+template <typename>
+class CommonPacket;
+
+template <typename>
+class CommonStream;
+
 namespace internal {
 
 template <typename LibObjPtrT>
@@ -20,6 +37,23 @@ void validateCreatedObjPtr(const LibObjPtrT libOjbPtr)
     }
 }
 
+template <typename LibObjT, typename DepObjT, typename ConstDepObjT>
+using DepType =
+    typename std::conditional<std::is_const<LibObjT>::value, ConstDepObjT, DepObjT>::type;
+
+template <typename LibObjT>
+using DepUserAttrs = DepType<LibObjT, CommonMapValue<bt_value>, CommonMapValue<const bt_value>>;
+
+template <typename LibObjT>
+using DepFc =
+    DepType<LibObjT, CommonFieldClass<bt_field_class>, CommonFieldClass<const bt_field_class>>;
+
+template <typename LibObjT>
+using DepPacket = DepType<LibObjT, CommonPacket<bt_packet>, CommonPacket<const bt_packet>>;
+
+template <typename LibObjT>
+using DepStream = DepType<LibObjT, CommonStream<bt_stream>, CommonStream<const bt_stream>>;
+
 template <typename ObjT>
 struct TypeDescr;
 
diff --git a/src/cpp-common/bt2/message.hpp b/src/cpp-common/bt2/message.hpp
index b3a6355b..1de0c481 100644
--- a/src/cpp-common/bt2/message.hpp
+++ b/src/cpp-common/bt2/message.hpp
@@ -230,10 +230,7 @@ class CommonStreamBeginningMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
+    using _Stream = internal::DepStream<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonStreamBeginningMessage<LibObjT>, LibObjT>;
@@ -348,10 +345,7 @@ class CommonStreamEndMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
+    using _Stream = internal::DepStream<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonStreamEndMessage<LibObjT>, LibObjT>;
@@ -465,10 +459,7 @@ class CommonPacketBeginningMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Packet =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonPacket<const bt_packet>,
-                                  CommonPacket<bt_packet>>::type;
+    using _Packet = internal::DepPacket<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonPacketBeginningMessage<LibObjT>, LibObjT>;
@@ -578,10 +569,7 @@ class CommonPacketEndMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Packet =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonPacket<const bt_packet>,
-                                  CommonPacket<bt_packet>>::type;
+    using _Packet = internal::DepPacket<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonPacketEndMessage<LibObjT>, LibObjT>;
@@ -690,10 +678,7 @@ class CommonEventMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Event =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonEvent<const bt_event>,
-                                  CommonEvent<bt_event>>::type;
+    using _Event = internal::DepType<LibObjT, CommonEvent<bt_event>, CommonEvent<const bt_event>>;
 
 public:
     using Shared = SharedMessage<CommonEventMessage<LibObjT>, LibObjT>;
@@ -793,10 +778,7 @@ class CommonDiscardedEventsMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
+    using _Stream = internal::DepStream<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonDiscardedEventsMessage<LibObjT>, LibObjT>;
@@ -927,10 +909,7 @@ class CommonDiscardedPacketsMessage final : public CommonMessage<LibObjT>
 private:
     using typename CommonMessage<LibObjT>::_LibObjPtr;
     using typename CommonMessage<LibObjT>::_ThisCommonMessage;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
+    using _Stream = internal::DepStream<LibObjT>;
 
 public:
     using Shared = SharedMessage<CommonDiscardedPacketsMessage<LibObjT>, LibObjT>;
diff --git a/src/cpp-common/bt2/trace-ir.hpp b/src/cpp-common/bt2/trace-ir.hpp
index 0542cd95..245a9d4f 100644
--- a/src/cpp-common/bt2/trace-ir.hpp
+++ b/src/cpp-common/bt2/trace-ir.hpp
@@ -121,6 +121,9 @@ struct CommonEventSpec<const bt_event> final
     }
 };
 
+template <typename LibObjT>
+using DepStructField = DepType<LibObjT, StructureField, ConstStructureField>;
+
 } /* namespace internal */
 
 template <typename LibObjT>
@@ -130,22 +133,13 @@ private:
     using typename BorrowedObject<LibObjT>::_ThisBorrowedObject;
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonEventSpec<LibObjT>;
-
-    using _Packet =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonPacket<const bt_packet>,
-                                  CommonPacket<bt_packet>>::type;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
-
-    using _StructureField = typename std::conditional<std::is_const<LibObjT>::value,
-                                                      ConstStructureField, StructureField>::type;
+    using _Packet = internal::DepPacket<LibObjT>;
+    using _Stream = internal::DepStream<LibObjT>;
+    using _StructureField = internal::DepStructField<LibObjT>;
 
 public:
-    using Class = typename std::conditional<std::is_const<LibObjT>::value,
-                                            CommonEventClass<const bt_event_class>,
-                                            CommonEventClass<bt_event_class>>::type;
+    using Class = internal::DepType<LibObjT, CommonEventClass<bt_event_class>,
+                                    CommonEventClass<const bt_event_class>>;
 
     explicit CommonEvent(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {
@@ -283,13 +277,8 @@ private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonPacketSpec<LibObjT>;
     using _ThisCommonPacket = CommonPacket<LibObjT>;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
-
-    using _StructureField = typename std::conditional<std::is_const<LibObjT>::value,
-                                                      ConstStructureField, StructureField>::type;
+    using _Stream = internal::DepStream<LibObjT>;
+    using _StructureField = internal::DepStructField<LibObjT>;
 
 public:
     using Shared = SharedObject<_ThisCommonPacket, LibObjT, internal::PacketRefFuncs>;
@@ -438,20 +427,14 @@ private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonStreamSpec<LibObjT>;
     using _ThisCommonStream = CommonStream<LibObjT>;
-
-    using _Trace =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonTrace<const bt_trace>,
-                                  CommonTrace<bt_trace>>::type;
+    using _Trace = internal::DepType<LibObjT, CommonTrace<bt_trace>, CommonTrace<const bt_trace>>;
 
 public:
     using Shared = SharedObject<_ThisCommonStream, LibObjT, internal::StreamRefFuncs>;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
-    using Class = typename std::conditional<std::is_const<LibObjT>::value,
-                                            CommonStreamClass<const bt_stream_class>,
-                                            CommonStreamClass<bt_stream_class>>::type;
-
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using Class = internal::DepType<LibObjT, CommonStreamClass<bt_stream_class>,
+                                    CommonStreamClass<const bt_stream_class>>;
 
     explicit CommonStream(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {
@@ -653,20 +636,14 @@ private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonTraceSpec<LibObjT>;
     using _ThisCommonTrace = CommonTrace<LibObjT>;
-
-    using _Stream =
-        typename std::conditional<std::is_const<LibObjT>::value, CommonStream<const bt_stream>,
-                                  CommonStream<bt_stream>>::type;
+    using _Stream = internal::DepStream<LibObjT>;
 
 public:
     using Shared = SharedObject<_ThisCommonTrace, LibObjT, internal::TraceRefFuncs>;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
-    using Class = typename std::conditional<std::is_const<LibObjT>::value,
-                                            CommonTraceClass<const bt_trace_class>,
-                                            CommonTraceClass<bt_trace_class>>::type;
-
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using Class = internal::DepType<LibObjT, CommonTraceClass<bt_trace_class>,
+                                    CommonTraceClass<const bt_trace_class>>;
 
     struct ConstEnvironmentEntry
     {
@@ -952,6 +929,9 @@ struct CommonEventClassSpec<const bt_event_class> final
     }
 };
 
+template <typename LibObjT>
+using DepStructFc = DepType<LibObjT, StructureFieldClass, ConstStructureFieldClass>;
+
 } /* namespace internal */
 
 template <typename LibObjT>
@@ -962,20 +942,15 @@ private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonEventClassSpec<LibObjT>;
     using _ThisCommonEventClass = CommonEventClass<LibObjT>;
+    using _StructureFieldClass = internal::DepStructFc<LibObjT>;
 
-    using _StreamClass = typename std::conditional<std::is_const<LibObjT>::value,
-                                                   CommonStreamClass<const bt_stream_class>,
-                                                   CommonStreamClass<bt_stream_class>>::type;
-
-    using _StructureFieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstStructureFieldClass,
-                                  StructureFieldClass>::type;
+    using _StreamClass = internal::DepType<LibObjT, CommonStreamClass<bt_stream_class>,
+                                           CommonStreamClass<const bt_stream_class>>;
 
 public:
     using Shared = SharedObject<_ThisCommonEventClass, LibObjT, internal::EventClassRefFuncs>;
 
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     enum class LogLevel
     {
@@ -1307,27 +1282,20 @@ private:
     using typename BorrowedObject<LibObjT>::_LibObjPtr;
     using _Spec = internal::CommonStreamClassSpec<LibObjT>;
     using _ThisCommonStreamClass = CommonStreamClass<LibObjT>;
+    using _StructureFieldClass = internal::DepStructFc<LibObjT>;
 
-    using _TraceClass = typename std::conditional<std::is_const<LibObjT>::value,
-                                                  CommonTraceClass<const bt_trace_class>,
-                                                  CommonTraceClass<bt_trace_class>>::type;
-
-    using _EventClass = typename std::conditional<std::is_const<LibObjT>::value,
-                                                  CommonEventClass<const bt_event_class>,
-                                                  CommonEventClass<bt_event_class>>::type;
+    using _TraceClass = internal::DepType<LibObjT, CommonTraceClass<bt_trace_class>,
+                                          CommonTraceClass<const bt_trace_class>>;
 
-    using _StructureFieldClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstStructureFieldClass,
-                                  StructureFieldClass>::type;
+    using _EventClass = internal::DepType<LibObjT, CommonEventClass<bt_event_class>,
+                                          CommonEventClass<const bt_event_class>>;
 
-    using _ClockClass =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstClockClass, ClockClass>::type;
+    using _ClockClass = internal::DepType<LibObjT, ClockClass, ConstClockClass>;
 
 public:
     using Shared = SharedObject<_ThisCommonStreamClass, LibObjT, internal::StreamClassRefFuncs>;
 
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonStreamClass(const _LibObjPtr libObjPtr) noexcept :
         _ThisBorrowedObject {libObjPtr}
@@ -1753,15 +1721,13 @@ private:
     using _Spec = internal::CommonTraceClassSpec<LibObjT>;
     using _ThisCommonTraceClass = CommonTraceClass<LibObjT>;
 
-    using _StreamClass = typename std::conditional<std::is_const<LibObjT>::value,
-                                                   CommonStreamClass<const bt_stream_class>,
-                                                   CommonStreamClass<bt_stream_class>>::type;
+    using _StreamClass = internal::DepType<LibObjT, CommonStreamClass<bt_stream_class>,
+                                           CommonStreamClass<const bt_stream_class>>;
 
 public:
     using Shared = SharedObject<_ThisCommonTraceClass, LibObjT, internal::TraceClassRefFuncs>;
 
-    using UserAttributes =
-        typename std::conditional<std::is_const<LibObjT>::value, ConstMapValue, MapValue>::type;
+    using UserAttributes = internal::DepUserAttrs<LibObjT>;
 
     explicit CommonTraceClass(const _LibObjPtr libObjPtr) noexcept : _ThisBorrowedObject {libObjPtr}
     {