diff --git a/src/index.ts b/src/index.ts
index 64040b3..e02b1c0 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -20,7 +20,7 @@ export default function parseArguments(
 
     //Iterate through all command line arguments. When we have read both name and value, verify the argument for correctness.
     //Show error if a name has no value afterwards, or a value has no name in front of it.
-    const lastOption = args.reduce(parseArgument.bind(null, { spec, outputArgs, requiredOptions, shortToLongLookup }));
+    const lastOption = args.reduce(parseArgument.bind(null, { spec, outputArgs, requiredOptions, shortToLongLookup }), '');
 
     // argumentName must be cleared to '' after the value is read, so if it is not an empty string, the value was missing
     if (lastOption !== '') {