Sum

:::info[Note] This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information. :::

Returns the integer sum of the values of the given Traversable

namespace HH\Lib\Math;

function sum(
  Traversable<int> $traversable,
): int;

For a float sum, see Math\sum_float().

Parameters

• Traversable<int>$traversable

Returns

• int

Examples

$v = vec[2, 1, 4];
$sum = Math\sum($v);
echo "Sum of array is $sum \n";