From dfe2cf3a40952953e77f731e8039fc64655622df Mon Sep 17 00:00:00 2001
From: Hendiadyoin1 <leon2002.la@gmail.com>
Date: Sun, 7 Nov 2021 14:34:55 +0100
Subject: [PATCH] AK: Add a Decay helper for Concepts

---
 AK/StdLibExtraDetails.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/AK/StdLibExtraDetails.h b/AK/StdLibExtraDetails.h
index 41f1ccc5302..85fb4342552 100644
--- a/AK/StdLibExtraDetails.h
+++ b/AK/StdLibExtraDetails.h
@@ -557,6 +557,22 @@ inline constexpr bool IsSpecializationOf = false;
 template<template<typename...> typename U, typename... Us>
 inline constexpr bool IsSpecializationOf<U<Us...>, U> = true;
 
+template<typename T>
+struct __decay {
+    typedef Detail::RemoveCVReference<T> type;
+};
+template<typename T>
+struct __decay<T[]> {
+    typedef T* type;
+};
+template<typename T, decltype(sizeof(T)) N>
+struct __decay<T[N]> {
+    typedef T* type;
+};
+// FIXME: Function decay
+template<typename T>
+using Decay = typename __decay<T>::type;
+
 }
 using AK::Detail::AddConst;
 using AK::Detail::AddLvalueReference;