From cdbed6970a08670b601187a4dc824da9ab74aa24 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sun, 4 Dec 2022 12:32:34 +0100
Subject: [PATCH] Result: Add expect_ variants of value() and release_value()

---
 luna/Result.h | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/luna/Result.h b/luna/Result.h
index ed99a04b..297fdec1 100644
--- a/luna/Result.h
+++ b/luna/Result.h
@@ -105,6 +105,12 @@ template <typename T> class Result
         return m_storage.fetch_reference();
     }
 
+    T expect_value(const char* reason)
+    {
+        expect(has_value(), reason);
+        return m_storage.fetch_reference();
+    }
+
     T value_or(T other)
     {
         if (has_value()) return m_storage.fetch_reference();
@@ -127,6 +133,15 @@ template <typename T> class Result
         return move(item);
     }
 
+    T expect_release_value(const char* reason)
+    {
+        expect(has_value(), reason);
+        T item = m_storage.fetch_reference();
+        m_has_value = false;
+        m_storage.destroy();
+        return move(item);
+    }
+
     ~Result()
     {
         if (has_value()) m_storage.destroy();
@@ -177,6 +192,7 @@ template <typename T> class Result
             fetch_reference().~T();
         }
     };
+
     Storage m_storage;
     int m_error;
     bool m_has_error;
@@ -243,12 +259,24 @@ template <> class Result<void>
         return;
     }
 
+    void expect_value(const char* reason)
+    {
+        expect(has_value(), reason);
+        return;
+    }
+
     void release_value()
     {
         expect(has_value(), "Result::release_value() called on a Result that holds an error");
         return;
     }
 
+    void expect_release_value(const char* reason)
+    {
+        expect(has_value(), reason);
+        return;
+    }
+
   private:
     int m_error;
     bool m_has_error;
@@ -262,5 +290,5 @@ template <> class Result<void>
     ({                                                                                                                 \
         auto _expr_rc = (expr);                                                                                        \
         if (_expr_rc.has_error()) return _expr_rc.release_error();                                                     \
-        _expr_rc.release_value();                                                                                      \
+        _expr_rc.expect_release_value("sanity check failed: has_error() returned false, yet result has no value");     \
     })