From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 29 Aug 2021 13:46:48 +0000 (+0300)
Subject: Deprecate various meta-programming constructs in favor of std ones
X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=commitdiff_plain;h=641a71730a0135fe647f6a230e9704d8b677f2c5

Deprecate various meta-programming constructs in favor of std ones
---

diff --git a/source/core/meta.h b/source/core/meta.h
index 6998c5d..3537301 100644
--- a/source/core/meta.h
+++ b/source/core/meta.h
@@ -2,42 +2,46 @@
 #define MSP_CORE_META_H_
 
 #include <cstddef>
+#include "attributes.h"
 
 namespace Msp {
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 template<typename T>
-struct RemoveConst
+struct DEPRECATED RemoveConst
 { typedef T Type; };
 
 template<typename T>
-struct RemoveConst<const T>
+struct DEPRECATED RemoveConst<const T>
 { typedef T Type; };
 
 
 template<typename T>
-struct RemoveReference
+struct DEPRECATED RemoveReference
 { typedef T Type; };
 
 template<typename T>
-struct RemoveReference<T &>
+struct DEPRECATED RemoveReference<T &>
 { typedef T Type; };
 
 
 template<typename T>
-struct RemoveConstReference
+struct DEPRECATED RemoveConstReference
 { typedef typename RemoveConst<typename RemoveReference<T>::Type>::Type Type; };
 
 
 template<bool c, typename R>
-struct EnableIf;
+struct DEPRECATED EnableIf;
 
 template<typename R>
-struct EnableIf<true, R>
+struct DEPRECATED EnableIf<true, R>
 { typedef R Yes; };
 
 template<typename R>
-struct EnableIf<false, R>
+struct DEPRECATED EnableIf<false, R>
 { typedef R No; };
+#pragma GCC diagnostic pop
 
 
 /**
diff --git a/source/core/variant.h b/source/core/variant.h
index 2dd9732..5109dbc 100644
--- a/source/core/variant.h
+++ b/source/core/variant.h
@@ -2,6 +2,7 @@
 #define MSP_CORE_VARIANT_H_
 
 #include <stdexcept>
+#include <type_traits>
 #include <typeinfo>
 #include "meta.h"
 
@@ -41,11 +42,11 @@ private:
 		virtual bool value_equals(const StoreBase &s) const { return value_equals_<T>(s); }
 
 		template<typename U>
-		typename EnableIf<IsEqualityComparable<U>::value, bool>::Yes value_equals_(const StoreBase &s) const
+		typename std::enable_if<IsEqualityComparable<U>::value, bool>::type value_equals_(const StoreBase &s) const
 		{ const Store<T> *t = dynamic_cast<const Store<T> *>(&s); return (t && t->data==data); }
 
 		template<typename U>
-		typename EnableIf<IsEqualityComparable<U>::value, bool>::No value_equals_(const StoreBase &) const
+		typename std::enable_if<!IsEqualityComparable<U>::value, bool>::type value_equals_(const StoreBase &) const
 		{ return false; }
 	};
 
@@ -54,7 +55,7 @@ private:
 public:
 	Variant(): store(0) { }
 	template<typename T>
-	Variant(const T &v): store(new Store<typename RemoveConst<T>::Type>(v)) { }
+	Variant(const T &v): store(new Store<typename std::remove_cv<T>::type>(v)) { }
 	Variant(const Variant &v): store(v.store ? v.store->clone() : 0) { }
 	~Variant() { delete store; }
 
@@ -62,7 +63,7 @@ public:
 	Variant &operator=(const T &v)
 	{
 		delete store;
-		store = new Store<typename RemoveConst<T>::Type>(v);
+		store = new Store<typename std::remove_cv<T>::type>(v);
 		return *this;
 	}
 
@@ -75,9 +76,9 @@ public:
 
 private:
 	template<typename T>
-	Store<typename RemoveConst<T>::Type> *get_typed_store() const
+	Store<typename std::remove_cv<T>::type> *get_typed_store() const
 	{
-		typedef typename RemoveConst<T>::Type NCT;
+		typedef typename std::remove_cv<T>::type NCT;
 		Store<NCT> *s = dynamic_cast<Store<NCT> *>(store);
 		if(!s)
 			throw type_mismatch(typeid(T), (store ? store->type_id() : typeid(void)));
@@ -100,7 +101,7 @@ public:
 	template<typename T>
 	bool check_type() const
 	{
-		return dynamic_cast<Store<typename RemoveConst<T>::Type> *>(store)!=0;
+		return dynamic_cast<Store<typename std::remove_cv<T>::type> *>(store)!=0;
 	}
 
 	bool check_same_type(const Variant &v) const
diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 2fc4be3..1c1f720 100644
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -10,12 +10,8 @@ namespace {
 
 using namespace Msp;
 
-template<typename T>
-struct IsSigned
-{ enum { result = !(static_cast<T>(-1)>0) }; };
-
 /* Helper to avoid warnings about an unsigned type never being < 0 */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct IsNegative
 { static bool eval(T v) { return v<0; } };
 
@@ -25,7 +21,7 @@ struct IsNegative<T, false>
 
 /* Helper to avoid errors about ambiguous function calls since there are no
 overloads of abs for unsigned types */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct Absolute
 { static T eval(T v) { return v<0 ? -v : v; } };
 
@@ -119,7 +115,7 @@ T str_to_int(const string &s, const Fmt &f)
 	bool neg = false;
 	if(*i=='-')
 	{
-		if(!IsSigned<T>::result)
+		if(is_unsigned<T>::value)
 			throw lexical_error(format("conversion of '%s' to unsigned integer", s));
 		neg = true;
 		++i;
diff --git a/source/strings/lexicalcast.h b/source/strings/lexicalcast.h
index 22b45e8..4f54a85 100644
--- a/source/strings/lexicalcast.h
+++ b/source/strings/lexicalcast.h
@@ -114,7 +114,7 @@ template<typename T> struct HasFormattedInput: Sfinae::Evaluate<CheckFormattedIn
 
 
 template<typename T>
-typename EnableIf<HasFormattedOutput<T>::value, void>::Yes
+typename std::enable_if<HasFormattedOutput<T>::value>::type
 operator<<(LexicalConverter &c, const T &v)
 {
 	std::ostringstream ss;
@@ -123,7 +123,7 @@ operator<<(LexicalConverter &c, const T &v)
 }
 
 template<typename T>
-typename EnableIf<HasFormattedInput<T>::value, void>::Yes
+typename std::enable_if<HasFormattedInput<T>::value>::type
 operator>>(const LexicalConverter &c, T &v)
 {
 	std::istringstream ss(c.get());