5 files changed, 53 insertions, 52 deletions

diff --git a/contributing.md b/contributing.md
index 5b0c79d..e4f075f 100644
--- a/contributing.md
+++ b/contributing.md
@@ -15,7 +15,11 @@ that you can click on to open them.
   `name/feature` (i.e. `loek/dll-so-poc` or `jaro/class2`)
 - The master branch is considered stable, and should always contain a
   working/compiling version of the project
+- Pull requests for new code include either automated tests for the new code or
+  an explanation as to why the code can not (reliably) be tested
+<!--
 - TODO: tagging / versions
+-->
 
 # Code style
 
@@ -790,6 +794,7 @@ that you can click on to open them.
   }
   ```
   </td></tr></table></details>
+- Do not implement new classes as singletons
 
 ## CMakeLists-specific
 
diff --git a/src/crepe/Asset.h b/src/crepe/Asset.h
deleted file mode 100644
index 9051c5e..0000000
--- a/src/crepe/Asset.h
+++ /dev/null
@@ -1,41 +0,0 @@
-#pragma once
-
-#include <fstream>
-#include <iostream>
-#include <string>
-
-namespace crepe {
-
-/**
- * \brief Asset location helper
- *
- * This class is used to locate and canonicalize paths to game asset files, and should *always*
- * be used when retrieving files from disk.
- */
-class Asset {
-public:
-	/**
-	 * \param src  Unique identifier to asset
-	 */
-	Asset(const std::string & src);
-
-public:
-	/**
-	 * \brief Get an input stream to the contents of this asset
-	 * \return Input stream with file contents
-	 */
-	std::istream & get_stream();
-	/**
-	 * \brief Get the canonical path to this asset
-	 * \return Canonical path to this asset
-	 */
-	const std::string & get_canonical() const;
-
-private:
-	//! Canonical path to asset
-	const std::string src;
-	//! File handle (stream)
-	std::ifstream file;
-};
-
-} // namespace crepe
diff --git a/src/crepe/api/Asset.h b/src/crepe/api/Asset.h
index 05dccba..685dd3a 100644
--- a/src/crepe/api/Asset.h
+++ b/src/crepe/api/Asset.h
@@ -1,7 +1,6 @@
 #pragma once
 
 #include <string>
-#include <unordered_map>
 
 namespace crepe {
 
@@ -52,7 +51,16 @@ private:
 
 namespace std {
 
+//! Hash helper struct
 template<> struct hash<const crepe::Asset> {
+	/**
+	 * \brief Hash operator for crepe::Asset
+	 *
+	 * This function hashes a crepe::Asset instance, allowing it to be used as a key in an \c
+	 * std::unordered_map.
+	 *
+	 * \returns Hash value
+	 */
 	size_t operator()(const crepe::Asset & asset) const noexcept;
 };
 
diff --git a/src/crepe/util/OptionalRef.h b/src/crepe/util/OptionalRef.h
index 1ad3a6d..8417a25 100644
--- a/src/crepe/util/OptionalRef.h
+++ b/src/crepe/util/OptionalRef.h
@@ -12,18 +12,51 @@ namespace crepe {
 template <typename T>
 class OptionalRef {
 public:
+	//! Initialize empty (nonexistant) reference
 	OptionalRef() = default;
-	OptionalRef(T &);
-  OptionalRef<T> & operator=(T &);
+	//! Initialize reference with value
+	OptionalRef(T & ref);
+	/**
+	 * \brief Assign new reference
+	 *
+	 * \param ref Reference to assign
+	 *
+	 * \return Reference to this (required for operator)
+	 */
+  OptionalRef<T> & operator=(T & ref);
+	/**
+	 * \brief Check if this reference is not empty
+	 *
+	 * \returns `true` if reference is set, or `false` if it is not
+	 */
 	explicit operator bool() const noexcept;
 
+	/**
+	 * \brief Assign new reference
+	 *
+	 * \param ref Reference to assign
+	 */
 	void set(T &) noexcept;
+	/**
+	 * \brief Retrieve this reference
+	 *
+	 * \returns Internal reference if it is set
+	 *
+	 * \throws std::runtime_error if this function is called while the reference it not set
+	 */
 	T & get() const;
+	/**
+	 * \brief Make this reference empty
+	 */
 	void clear() noexcept;
 
+	//! Copy constructor
   OptionalRef(const OptionalRef<T> &);
+	//! Move constructor
   OptionalRef(OptionalRef<T> &&);
+	//! Copy assignment
   OptionalRef<T> & operator=(const OptionalRef<T> &);
+	//! Move assignment
   OptionalRef<T> & operator=(OptionalRef<T> &&);
 
 private:
diff --git a/src/example/audio_internal.cpp b/src/example/audio_internal.cpp
index e23d485..f3bf349 100644
--- a/src/example/audio_internal.cpp
+++ b/src/example/audio_internal.cpp
@@ -29,15 +29,11 @@ int main() {
 	SoundContext ctx{};
 	Sound sound{ctx};
 	// Load a background track (Ogg Vorbis)
-	auto _bgm = sound.clone(Asset{"mwe/audio/bgm.ogg"});
-	Sound & bgm = *dynamic_cast<Sound *>(_bgm.get());
+	auto bgm = Sound("mwe/audio/bgm.ogg");
 	// Load three short samples (WAV)
-	auto _sfx1 = sound.clone(Asset{"mwe/audio/sfx1.wav"});
-	Sound & sfx1 = *dynamic_cast<Sound *>(_sfx1.get());
-	auto _sfx2 = sound.clone(Asset{"mwe/audio/sfx2.wav"});
-	Sound & sfx2 = *dynamic_cast<Sound *>(_sfx2.get());
-	auto _sfx3 = sound.clone(Asset{"mwe/audio/sfx3.wav"});
-	Sound & sfx3 = *dynamic_cast<Sound *>(_sfx3.get());
+	auto sfx1 = Sound("mwe/audio/sfx1.wav");
+	auto sfx2 = Sound("mwe/audio/sfx2.wav");
+	auto sfx3 = Sound("mwe/audio/sfx3.wav");
 
 	// Start the background track
 	bgm.play();