diff --git a/src/backend/mi2/mi2.ts b/src/backend/mi2/mi2.ts
index 2b6cfbf..e29221d 100644
--- a/src/backend/mi2/mi2.ts
+++ b/src/backend/mi2/mi2.ts
@@ -573,15 +573,13 @@ export class MI2 extends EventEmitter implements IBackend {
 	}
 
 	sendUserInput(command: string): Thenable<any> {
-		return new Promise((resolve, reject) => {
-			if (command.startsWith("-")) {
-				this.sendCommand(command.substr(1)).then(resolve, reject);
-			}
-			else {
-				this.sendRaw(command);
-				resolve(undefined);
-			}
-		});
+		if (command.startsWith("-")) {
+			return this.sendCommand(command.substr(1));
+		}
+		else {
+			this.sendRaw(command);
+			return Promise.resolve(undefined);
+		}
 	}
 
 	sendRaw(raw: string) {
diff --git a/src/mibase.ts b/src/mibase.ts
index 13ec0a3..6c0a9bc 100644
--- a/src/mibase.ts
+++ b/src/mibase.ts
@@ -348,8 +348,16 @@ export class MI2DebugSession extends DebugSession {
 			});
 		else {
 			this.miDebugger.sendUserInput(args.expression).then(output => {
-				if (output)
-					response.body.result = JSON.stringify(output);
+				if (typeof output == "undefined")
+					response.body = {
+						result: "",
+						variablesReference: 0
+					};
+				else
+					response.body = {
+						result: JSON.stringify(output),
+						variablesReference: 0
+					};
 				this.sendResponse(response);
 			}, msg => {
 				this.sendErrorResponse(response, 8, msg.toString());