encode minor performance optimization

msgpack#172

Author: buu700

src/encode.ts

@@ -36,6 +36,7 @@ export type EncodeOptions<ContextType = undefined> = Partial<
   ContextOf<ContextType>;
 
 const defaultEncodeOptions: EncodeOptions = {};
+const defaultEncoder = new Encoder();
 
 /**
  * It encodes `value` in the MessagePack format and
@@ -47,7 +48,7 @@ export function encode<ContextType = undefined>(
   value: unknown,
   options: EncodeOptions<SplitUndefined<ContextType>> = defaultEncodeOptions as any,
 ): Uint8Array {
-  const encoder = new Encoder(
+  const encoder = !options ? defaultEncoder : new Encoder(
     options.extensionCodec,
     (options as typeof options & { context: any }).context,
     options.maxDepth,