Add functional options to command executor.

CHANGELOG.md

@@ -14,10 +14,12 @@ The format is based on [Keep a Changelog], and this project adheres to
 
 ### Added
 
-- **[ENGINE BC]** Added `...RegisterAggregateOption` parameter to `ApplicationConfigurer.RegisterAggregate()`
-- **[ENGINE BC]** Added `...RegisterProcessOption` parameter to `ApplicationConfigurer.RegisterProcess()`
-- **[ENGINE BC]** Added `...RegisterIntegrationOption` parameter to `ApplicationConfigurer.RegisterIntegration()`
-- **[ENGINE BC]** Added `...RegisterProjectionOption` parameter to `ApplicationConfigurer.RegisterProjection()`
+- **[ENGINE BC]** Added functional options to the following methods and functions:
+  - `ApplicationConfigurer.RegisterAggregate()`
+  - `ApplicationConfigurer.RegisterProcess()`
+  - `ApplicationConfigurer.RegisterIntegration()`
+  - `ApplicationConfigurer.RegisterProjection()`
+  - `CommandExecutor.ExecuteCommand()`
 
 ### Removed
 

external.go → executor.go

@@ -16,5 +16,9 @@ type CommandExecutor interface {
 	// The application SHOULD assume that the command is executed
 	// asynchronously; it has not necessarily executed by the time the method
 	// returns.
-	ExecuteCommand(context.Context, Command) error
+	ExecuteCommand(context.Context, Command, ...ExecuteCommandOption) error
 }
+
+// ExecuteCommandOption is an option that affects the behavior of a call to the
+// ExecuteCommand() method of the [CommandExecutor] interface.
+type ExecuteCommandOption struct{}

projection.go

@@ -159,7 +159,7 @@ type ProjectionCompactScope interface {
 type NoCompactBehavior struct{}
 
 // Compact does nothing.
-func (NoCompactBehavior) Compact(ctx context.Context, s ProjectionCompactScope) error {
+func (NoCompactBehavior) Compact(context.Context, ProjectionCompactScope) error {
 	return nil
 }