# Function chain Wrap any value in a chain, allowing to perform chained operations on the value. All methods available in the math.js library can be called upon the chain, and then will be evaluated with the value itself as first argument. The chain can be closed by executing `chain.done()`, which returns the final value. The chain has a number of special functions: - `done()` Finalize the chain and return the chain's value. - `valueOf()` The same as `done()` - `toString()` Executes `math.format()` onto the chain's value, returning a string representation of the value. ## Syntax ```js math.chain(value) ``` ### Parameters Parameter | Type | Description --------- | ---- | ----------- `value` | * | A value of any type on which to start a chained operation. ### Returns Type | Description ---- | ----------- math.Chain | The created chain ## Examples ```js math.chain(3) .add(4) .subtract(2) .done() // 5 math.chain( [[1, 2], [3, 4]] ) .subset(math.index(0, 0), 8) .multiply(3) .done() // [[24, 6], [9, 12]] ```