From bdad497c3efc08a3402463b0bd5561b61e81f0b8 Mon Sep 17 00:00:00 2001
From: Rangi42 <sylvie.oukaour+rangi42@gmail.com>
Date: Sat, 15 Feb 2025 11:08:14 +0100
Subject: [PATCH] C++20 derives `!=` from `operator==` as `!` of `==`

---
 include/gfx/rgba.hpp    | 1 -
 include/itertools.hpp   | 5 -----
 src/gfx/pal_packing.cpp | 3 ++-
 src/gfx/process.cpp     | 1 -
 4 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/include/gfx/rgba.hpp b/include/gfx/rgba.hpp
index be0ea510e..b58c93e5a 100644
--- a/include/gfx/rgba.hpp
+++ b/include/gfx/rgba.hpp
@@ -37,7 +37,6 @@ struct Rgba {
 		return shl(red, 24) | shl(green, 16) | shl(blue, 8) | shl(alpha, 0);
 	}
 	bool operator==(Rgba const &rhs) const { return toCSS() == rhs.toCSS(); }
-	bool operator!=(Rgba const &rhs) const { return toCSS() != rhs.toCSS(); }
 
 	// CGB colors are RGB555, so we use bit 15 to signify that the color is transparent instead
 	// Since the rest of the bits don't matter then, we return 0x8000 exactly.
diff --git a/include/itertools.hpp b/include/itertools.hpp
index 4629b5216..805a18382 100644
--- a/include/itertools.hpp
+++ b/include/itertools.hpp
@@ -25,7 +25,6 @@ class EnumSeq {
 		auto operator*() const { return _value; }
 
 		bool operator==(Iterator const &rhs) const { return _value == rhs._value; }
-		bool operator!=(Iterator const &rhs) const { return _value != rhs._value; }
 	};
 
 public:
@@ -59,10 +58,6 @@ class ZipIterator {
 	bool operator==(ZipIterator const &rhs) const {
 		return std::get<0>(_iters) == std::get<0>(rhs._iters);
 	}
-
-	bool operator!=(ZipIterator const &rhs) const {
-		return std::get<0>(_iters) != std::get<0>(rhs._iters);
-	}
 };
 
 template<typename... Ts>
diff --git a/src/gfx/pal_packing.cpp b/src/gfx/pal_packing.cpp
index 869299c22..083e6efa9 100644
--- a/src/gfx/pal_packing.cpp
+++ b/src/gfx/pal_packing.cpp
@@ -87,7 +87,7 @@ class AssignedProtos {
 		Iter() = default;
 
 		bool operator==(Iter const &other) const { return _iter == other._iter; }
-		bool operator!=(Iter const &other) const { return !(*this == other); }
+
 		Iter &operator++() {
 			++_iter;
 			skipEmpty();
@@ -98,6 +98,7 @@ class AssignedProtos {
 			++(*this);
 			return it;
 		}
+
 		reference operator*() const {
 			assume((*_iter).has_value());
 			return **_iter;
diff --git a/src/gfx/process.cpp b/src/gfx/process.cpp
index 646a49f9c..c1753c1e3 100644
--- a/src/gfx/process.cpp
+++ b/src/gfx/process.cpp
@@ -466,7 +466,6 @@ class Png {
 			}
 
 			bool operator==(Iterator const &rhs) const { return coords() == rhs.coords(); }
-			bool operator!=(Iterator const &rhs) const { return coords() != rhs.coords(); }
 		};
 
 	public: