Handle null and undefined values

Author: brunolemos

src/index.js

@@ -12,6 +12,9 @@ const boolRe = /^true|false$/i;
 export const transformRawValue = (input) => {
   const value = input.trim();
 
+  if (value === 'null') return null
+  if (value === 'undefined') return undefined
+
   const numberMatch = value.match(numberOrLengthRe);
   if (numberMatch !== null) return Number(numberMatch[1]);