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src/lib/utils.ts

@@ -610,3 +610,15 @@ export async function readFileToText(file: File): Promise<string> {
         reader.readAsText(file);
     })
 }
+
+
+export function nextLetter(s: string): string {
+    return s.replace(/([a-zA-Z])[^a-zA-Z]*$/, function(a) {
+        var c = a.charCodeAt(0);
+        switch (c) {
+            case 90: return 'A';
+            case 122: return 'a';
+            default: return String.fromCharCode(++c);
+        }
+    });
+}