Use more concise alias versions of standard type traits in base::Bind.
This gets rid of a noticeable amount of "typename std::some_trait<...>::type"
boilerplate. In a few places, the std::integral_constant conversion operator
is used to replace ::value in cases where it makes things look more concise.
Change-Id: Ib733e9e24650452dc7d6c276e51fec2713e5c30d
Reviewed-on: https://chromium-review.googlesource.com/617300
Commit-Queue: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#494974}
CrOS-Libchrome-Original-Commit: 35a31743fdc9006d5424fd2e1e15f6aba0a3c30c
diff --git a/base/bind_internal.h b/base/bind_internal.h
index 185e00d..c36b153 100644
--- a/base/bind_internal.h
+++ b/base/bind_internal.h
@@ -98,9 +98,9 @@
// parameters recursively.
template <typename T, typename... Args>
struct HasRefCountedTypeAsRawPtr<T, Args...>
- : std::conditional<NeedsScopedRefptrButGetsRawPtr<T>::value,
- std::true_type,
- HasRefCountedTypeAsRawPtr<Args...>>::type {};
+ : std::conditional_t<NeedsScopedRefptrButGetsRawPtr<T>::value,
+ std::true_type,
+ HasRefCountedTypeAsRawPtr<Args...>> {};
// ForceVoidReturn<>
//
@@ -124,9 +124,8 @@
// base::Bind(), based on the fact that captureless lambdas can be convertible
// to the function type while capturing lambdas can't.
template <typename Functor>
-struct FunctorTraits<
- Functor,
- typename std::enable_if<IsConvertibleToRunType<Functor>::value>::type> {
+struct FunctorTraits<Functor,
+ std::enable_if_t<IsConvertibleToRunType<Functor>::value>> {
using RunType = ExtractCallableRunType<Functor>;
static constexpr bool is_method = false;
static constexpr bool is_nullable = false;
@@ -243,7 +242,7 @@
};
template <typename Functor>
-using MakeFunctorTraits = FunctorTraits<typename std::decay<Functor>::type>;
+using MakeFunctorTraits = FunctorTraits<std::decay_t<Functor>>;
// InvokeHelper<>
//
@@ -328,12 +327,10 @@
UnboundArgs&&... unbound_args) {
static constexpr bool is_method = MakeFunctorTraits<Functor>::is_method;
- using DecayedArgsTuple = typename std::decay<BoundArgsTuple>::type;
+ using DecayedArgsTuple = std::decay_t<BoundArgsTuple>;
static constexpr bool is_weak_call =
IsWeakMethod<is_method,
- typename std::tuple_element<
- indices,
- DecayedArgsTuple>::type...>::value;
+ std::tuple_element_t<indices, DecayedArgsTuple>...>();
return InvokeHelper<is_weak_call, R>::MakeItSo(
std::forward<Functor>(functor),
@@ -372,14 +369,14 @@
};
template <typename Functor>
-typename std::enable_if<FunctorTraits<Functor>::is_nullable, bool>::type
-IsNull(const Functor& functor) {
+std::enable_if_t<FunctorTraits<Functor>::is_nullable, bool> IsNull(
+ const Functor& functor) {
return !functor;
}
template <typename Functor>
-typename std::enable_if<!FunctorTraits<Functor>::is_nullable, bool>::type
-IsNull(const Functor&) {
+std::enable_if_t<!FunctorTraits<Functor>::is_nullable, bool> IsNull(
+ const Functor&) {
return false;
}
@@ -489,38 +486,33 @@
template <typename Functor, typename... BoundArgs>
struct MakeBindStateTypeImpl<false, Functor, BoundArgs...> {
- static_assert(!HasRefCountedTypeAsRawPtr<
- typename std::decay<BoundArgs>::type...>::value,
+ static_assert(!HasRefCountedTypeAsRawPtr<std::decay_t<BoundArgs>...>::value,
"A parameter is a refcounted type and needs scoped_refptr.");
- using Type = BindState<typename std::decay<Functor>::type,
- typename std::decay<BoundArgs>::type...>;
+ using Type = BindState<std::decay_t<Functor>, std::decay_t<BoundArgs>...>;
};
template <typename Functor>
struct MakeBindStateTypeImpl<true, Functor> {
- using Type = BindState<typename std::decay<Functor>::type>;
+ using Type = BindState<std::decay_t<Functor>>;
};
template <typename Functor, typename Receiver, typename... BoundArgs>
struct MakeBindStateTypeImpl<true, Functor, Receiver, BoundArgs...> {
- static_assert(
- !std::is_array<typename std::remove_reference<Receiver>::type>::value,
- "First bound argument to a method cannot be an array.");
- static_assert(!HasRefCountedTypeAsRawPtr<
- typename std::decay<BoundArgs>::type...>::value,
+ static_assert(!std::is_array<std::remove_reference_t<Receiver>>::value,
+ "First bound argument to a method cannot be an array.");
+ static_assert(!HasRefCountedTypeAsRawPtr<std::decay_t<BoundArgs>...>::value,
"A parameter is a refcounted type and needs scoped_refptr.");
private:
- using DecayedReceiver = typename std::decay<Receiver>::type;
+ using DecayedReceiver = std::decay_t<Receiver>;
public:
using Type = BindState<
- typename std::decay<Functor>::type,
- typename std::conditional<
- std::is_pointer<DecayedReceiver>::value,
- scoped_refptr<typename std::remove_pointer<DecayedReceiver>::type>,
- DecayedReceiver>::type,
- typename std::decay<BoundArgs>::type...>;
+ std::decay_t<Functor>,
+ std::conditional_t<std::is_pointer<DecayedReceiver>::value,
+ scoped_refptr<std::remove_pointer_t<DecayedReceiver>>,
+ DecayedReceiver>,
+ std::decay_t<BoundArgs>...>;
};
template <typename Functor, typename... BoundArgs>