cursed: add Mutex type

Signed-off-by: Xe Iaso <me@xeiaso.net>

2 files changed, 30 insertions, 0 deletions

diff --git a/cursed/doc.go b/cursed/doc.go
index b613846..4395a3f 100644
--- a/cursed/doc.go
+++ b/cursed/doc.go
@@ -1,12 +1,20 @@
 // Package cursed contains code that should never be used by anyone.
 //
 // This place is a message... and part of a system of messages... pay attention to it!
+//
 // Sending this message was important to us. We considered ourselves to be a powerful culture.
+//
 // This place is not a place of honor... no highly esteemed deed is commemorated here... nothing valued is here.
+//
 // What is here was dangerous and repulsive to us. This message is a warning about danger.
+//
 // The danger is in a particular location... it increases towards a center... the center of danger is here... of a particular size and shape, and below us.
+//
 // The danger is still present, in your time, as it was in ours.
+//
 // The danger is to the body, and it can kill.
+//
 // The form of the danger is an emanation of energy.
+//
 // The danger is unleashed only if you substantially disturb this place physically. This place is best shunned and left uninhabited.
 package cursed
diff --git a/cursed/mutex.go b/cursed/mutex.go
new file mode 100644
index 0000000..82fe58f
--- /dev/null
+++ b/cursed/mutex.go
@@ -0,0 +1,22 @@
+package cursed
+
+import "sync"
+
+// Mutex is a generic locking container for Go much like Rust's std::sync::Mutex<T>.
+//
+// It differs from a normal sync.Mutex because it guards a value instead of just
+// being something you lock and unlock to guard another value. When you are done with
+// the value, call the function return to re-lock the mutex.
+type Mutex[T any] struct {
+	val  T
+	lock sync.Mutex
+}
+
+func NewMutex[T any](val T) *Mutex[T] {
+	return &Mutex[T]{val: val}
+}
+
+func (mu *Mutex[T]) Unlock() (T, func()) {
+	mu.lock.Lock()
+	return mu.val, func() { mu.lock.Unlock() }
+}