From 7aa38d0b564907763c0fb9c11578369523e3c1a2 Mon Sep 17 00:00:00 2001
From: "Dirk-Jan C. Binnema" <djcb@djcbsoftware.nl>
Date: Wed, 9 Aug 2023 20:13:12 +0300
Subject: [PATCH] option/result: add "unwrap"

Sprinkle some more Rust on Option & Result
---
 lib/utils/mu-option.hh | 11 +++++++++++
 lib/utils/mu-result.hh |  4 ++--
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/utils/mu-option.hh b/lib/utils/mu-option.hh
index 3ca683e0..32b1beea 100644
--- a/lib/utils/mu-option.hh
+++ b/lib/utils/mu-option.hh
@@ -21,6 +21,7 @@
 #define MU_OPTION__
 
 #include <tl/optional.hpp>
+#include <stdexcept>
 #include <string>
 
 namespace Mu {
@@ -36,6 +37,16 @@ Some(T&& t)
 }
 constexpr auto Nothing = tl::nullopt; // 'None' is already taken.
 
+template<typename T> T
+unwrap(Option<T>&& res)
+{
+	if (!!res)
+		return std::move(res.value());
+	else
+		throw std::runtime_error("failure is not an option");
+}
+
+
 /**
  * Maybe create a string from a const char pointer.
  *
diff --git a/lib/utils/mu-result.hh b/lib/utils/mu-result.hh
index c7d6aa30..46346ed5 100644
--- a/lib/utils/mu-result.hh
+++ b/lib/utils/mu-result.hh
@@ -106,8 +106,8 @@ Err(Error::Code code, GError **err, fmt::format_string<T...> frm, T&&... args)
 }
 
 
-template<typename T>
-T unwrap(Result<T>&& res)
+template<typename T> T
+unwrap(Result<T>&& res)
 {
 	if (!!res)
 		return std::move(res.value());