From 96b36203a285baa942e2ca8e4e2d957879d00ba8 Mon Sep 17 00:00:00 2001
From: Ali Mohammad Pur <ali.mpfard@gmail.com>
Date: Sat, 10 Dec 2022 19:36:32 +0330
Subject: [PATCH] AK: Add Optional::lazy_emplace(Callable)

This makes it possible to emplace using a given function instead of
passing constructor arguments.
---
 AK/Optional.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/AK/Optional.h b/AK/Optional.h
index 08f659dce4..6acf64f384 100644
--- a/AK/Optional.h
+++ b/AK/Optional.h
@@ -200,6 +200,14 @@ public:
         new (&m_storage) T(forward<Parameters>(parameters)...);
     }
 
+    template<typename Callable>
+    ALWAYS_INLINE void lazy_emplace(Callable callable)
+    {
+        clear();
+        m_has_value = true;
+        new (&m_storage) T { callable() };
+    }
+
     [[nodiscard]] ALWAYS_INLINE bool has_value() const { return m_has_value; }
 
     [[nodiscard]] ALWAYS_INLINE T& value() &