Fix type to include undefined

diff --git a/src/core.js b/src/core.js
index be55c12e92f6fa2603c5bdfea5341160a91315e1..ce917f814df5aa7373833bf3db2760cad2d1a26b 100644 (file)
--- a/src/core.js
+++ b/src/core.js
@@ -222,8 +222,8 @@ export class CSVReader {
  */
 
 /**
- * A row or rows of output CSV data, or `null` to not output anything.
- * @typedef {Array<Array<any>>|Array<any>|ArrayLike<any>|string|null} TransformationOutput
+ * A row or rows of output CSV data, or `null` or `undefined` to not output anything.
+ * @typedef {Array<Array<any>>|Array<any>|ArrayLike<any>|string|null|undefined} TransformationOutput
  */
 
 /**