transact • tldraw Docs

Like transaction, but does not create a new transaction if there is already one in progress. This is the preferred way to batch state updates when you don't need the rollback functionality.

function transact<T>(fn: () => T): T;

Example

const count = atom("count", 0);
const doubled = atom("doubled", 0);

react("update doubled", () => {
  console.log(`Count: ${count.get()}, Doubled: ${doubled.get()}`);
});

// This batches both updates into a single reaction
transact(() => {
  count.set(5);
  doubled.set(count.get() * 2);
});
// Logs: "Count: 5, Doubled: 10"

Parameters

Name	Description
`fn`	`() => T;` The function to run in a transaction

Returns

T;

The return value of the function