| --- |
| page_title: setunion - Functions - Configuration Language |
| description: |- |
| The setunion function takes multiple sets and produces a single set |
| containing the elements from all of the given sets. |
| --- |
| |
| # `setunion` Function |
| |
| The `setunion` function takes multiple sets and produces a single set |
| containing the elements from all of the given sets. In other words, it |
| computes the [union](https://en.wikipedia.org/wiki/Union_\(set_theory\)) of |
| the sets. |
| |
| ```hcl |
| setunion(sets...) |
| ``` |
| |
| ## Examples |
| |
| ``` |
| > setunion(["a", "b"], ["b", "c"], ["d"]) |
| [ |
| "d", |
| "b", |
| "c", |
| "a", |
| ] |
| ``` |
| |
| The given arguments are converted to sets, so the result is also a set and |
| the ordering of the given elements is not preserved. |
| |
| ## Related Functions |
| |
| * [`contains`](/terraform/language/functions/contains) tests whether a given list or set contains |
| a given element value. |
| * [`setintersection`](/terraform/language/functions/setintersection) computes the _intersection_ of |
| multiple sets. |
| * [`setproduct`](/terraform/language/functions/setproduct) computes the _Cartesian product_ of multiple |
| sets. |
| * [`setsubtract`](/terraform/language/functions/setsubtract) computes the _relative complement_ of two sets |
