use https://github.com/nunocoracao/blowfish.git

themes/blowfish/assets/lib/mermaid/utils/imperativeState.d.ts

@@ -0,0 +1,32 @@
+/**
+ * Resettable state storage.
+ * @example
+ * ```
+ * const state = new ImperativeState(() => {
+ *   foo: undefined as string | undefined,
+ *   bar: [] as number[],
+ *   baz: 1 as number | undefined,
+ * });
+ *
+ * state.records.foo = "hi";
+ * console.log(state.records.foo); // prints "hi";
+ * state.reset();
+ * console.log(state.records.foo); // prints "default";
+ *
+ * // typeof state.records:
+ * // {
+ * //   foo: string | undefined, // actual: undefined
+ * //   bar: number[],           // actual: []
+ * //   baz: number | undefined, // actual: 1
+ * // }
+ * ```
+ */
+export declare class ImperativeState<S extends Record<string, unknown>> {
+    private init;
+    records: S;
+    /**
+     * @param init - Function that creates the default state.
+     */
+    constructor(init: () => S);
+    reset(): void;
+}