init repo

options.go

@@ -0,0 +1,71 @@
+package actor
+
+const (
+	defaultFixedCapacity = 64
+	defaultBatchSize     = 64
+)
+
+type configuration[T any] struct {
+	fixedCapacity int
+	batchSize     int
+	onPanic       func(T, any, []byte)
+	dispatcher    Dispatcher
+}
+
+// Option configures an Actor during construction.
+type Option[T any] func(*configuration[T])
+
+// WithFixedCapacity sets the number of retained mailbox nodes. The default is
+// 64. This is not a mailbox limit: further messages use dynamic nodes.
+func WithFixedCapacity[T any](capacity int) Option[T] {
+	return func(c *configuration[T]) { c.fixedCapacity = capacity }
+}
+
+// WithBatchSize sets how many messages are consumed between calls to
+// runtime.Gosched. Long pending-batch reversals also yield at this interval.
+// The default is 64, independent of the dispatcher.
+func WithBatchSize[T any](size int) Option[T] {
+	return func(c *configuration[T]) { c.batchSize = size }
+}
+
+// WithPanicHandler sets an optional callback for handler panics. It receives the
+// message, the recovered value, and a stack trace. Its own panics are recovered.
+// A nil callback disables panic reporting; messages still continue to drain.
+func WithPanicHandler[T any](handler func(message T, value any, stack []byte)) Option[T] {
+	return func(c *configuration[T]) { c.onPanic = handler }
+}
+
+// WithDispatcher chooses the construction-time scheduling policy. The default
+// dispatcher runs inline. New rejects a nil interface or nil DispatcherFunc.
+// Custom typed-nil implementations must themselves satisfy the Dispatcher
+// contract; their validity is the caller's responsibility.
+func WithDispatcher[T any](dispatcher Dispatcher) Option[T] {
+	return func(c *configuration[T]) { c.dispatcher = dispatcher }
+}
+
+func configure[T any](opts []Option[T]) configuration[T] {
+	c := configuration[T]{
+		fixedCapacity: defaultFixedCapacity,
+		batchSize:     defaultBatchSize,
+		dispatcher:    inlineDispatcher{},
+	}
+	for _, opt := range opts {
+		if opt == nil {
+			panic("actor: nil option")
+		}
+		opt(&c)
+	}
+	if c.fixedCapacity <= 0 {
+		panic("actor: fixed capacity must be positive")
+	}
+	if c.batchSize <= 0 {
+		panic("actor: batch size must be positive")
+	}
+	if c.dispatcher == nil {
+		panic("actor: nil dispatcher")
+	}
+	if f, ok := c.dispatcher.(DispatcherFunc); ok && f == nil {
+		panic("actor: nil dispatcher function")
+	}
+	return c
+}