| --- |
| page_title: setsubtract - Functions - Configuration Language |
| description: |- |
| The setsubtract function returns a new set containing the elements |
| from the first set that are not present in the second set |
| --- |
| |
| # `setsubtract` Function |
| |
| The `setsubtract` function returns a new set containing the elements from the first set that are not present in the second set. In other words, it computes the |
| [relative complement](https://en.wikipedia.org/wiki/Complement_\(set_theory\)#Relative_complement) of the second set. |
| |
| ```hcl |
| setsubtract(a, b) |
| ``` |
| |
| ## Examples |
| |
| ``` |
| > setsubtract(["a", "b", "c"], ["a", "c"]) |
| toset([ |
| "b", |
| ]) |
| ``` |
| |
| ### Set Difference (Symmetric Difference) |
| |
| ``` |
| > setunion(setsubtract(["a", "b", "c"], ["a", "c", "d"]), setsubtract(["a", "c", "d"], ["a", "b", "c"])) |
| toset([ |
| "b", |
| "d", |
| ]) |
| ``` |
| |
| ## Related Functions |
| |
| * [`setintersection`](/terraform/language/functions/setintersection) computes the _intersection_ of multiple sets |
| * [`setproduct`](/terraform/language/functions/setproduct) computes the _Cartesian product_ of multiple |
| sets. |
| * [`setunion`](/terraform/language/functions/setunion) computes the _union_ of |
| multiple sets. |
