diff --git a/src/Editor.php b/src/Editor.php
index e3849d7..8b28b46 100644
--- a/src/Editor.php
+++ b/src/Editor.php
@@ -250,6 +250,17 @@ class Editor {
 		$this->updateRow($this->rows[$at]);
 	}
 
+	protected function rowInsertChar(Row $row, int $at, string $c)
+	{
+		if ($at < 0 || $at > $row->size)
+		{
+			$at = $row->size;
+		}
+
+		$row->chars[$at] = $c;
+		$this->updateRow($row);
+	}
+
 	// ------------------------------------------------------------------------
 	// ! File I/O
 	// ------------------------------------------------------------------------