📄 tanstack/pacer/latest/docs/reference/functions/queue

function queue<TValue>(fn, initialOptions): (item, position, runOnItemsChange) => boolean;


function queue<TValue>(fn, initialOptions): (item, position, runOnItemsChange) => boolean;

Defined in: queuer.ts:730

Creates a queue that processes items immediately upon addition. Items are processed sequentially in FIFO order by default.

This synchronous version is lighter weight and often all you need - upgrade to asyncQueue when you need promises, retry support, abort capabilities, concurrent execution, or advanced error handling.

State Management:

Uses TanStack Store for reactive state management
Use initialState to provide initial state values when creating the queuer
Use onExecute callback to react to item execution and implement custom logic
Use onItemsChange callback to react to items being added or removed from the queue
Use onExpire callback to react to items expiring and implement custom logic
Use onReject callback to react to items being rejected when the queue is full
The state includes execution count, expiration count, rejection count, and isRunning status
State can be accessed via the underlying Queuer instance's store.state property
When using framework adapters (React/Solid), state is accessed from the hook's state property

Example usage:

// Basic sequential processing
const processItems = queue<number>((n) => console.log(n), {
  wait: 1000,
  onItemsChange: (queuer) => console.log(queuer.peekAllItems())
});
processItems(1); // Logs: 1
processItems(2); // Logs: 2 after 1 completes

// Priority queue
const processPriority = queue<number>((n) => console.log(n), {
  getPriority: n => n // Higher numbers processed first
});
processPriority(1);
processPriority(3); // Processed before 1


// Basic sequential processing
const processItems = queue<number>((n) => console.log(n), {
  wait: 1000,
  onItemsChange: (queuer) => console.log(queuer.peekAllItems())
});
processItems(1); // Logs: 1
processItems(2); // Logs: 2 after 1 completes

// Priority queue
const processPriority = queue<number>((n) => console.log(n), {
  getPriority: n => n // Higher numbers processed first
});
processPriority(1);
processPriority(3); // Processed before 1

Type Parameters
--------------- ### TValue

TValue

Parameters
---------- ### fn

(item) => void

### initialOptions

QueuerOptions <TValue>

Returns
-------

(
   item, 
   position, 
   runOnItemsChange): boolean;


(
   item, 
   position, 
   runOnItemsChange): boolean;

Adds an item to the queue. If the queue is full, the item is rejected and onReject is called. Items can be inserted based on priority or at the front/back depending on configuration.

Returns true if the item was added, false if the queue is full.

Example usage:

queuer.addItem('task');
queuer.addItem('task2', 'front');


queuer.addItem('task');
queuer.addItem('task2', 'front');

### Parameters #### item

TValue

#### position

QueuePosition = ...

#### runOnItemsChange

boolean = true

boolean

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