50 lines
1.3 KiB
Markdown
50 lines
1.3 KiB
Markdown
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---
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layout: "functions"
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page_title: "setsubtract - Functions - Configuration Language"
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sidebar_current: "docs-funcs-collection-setsubtract"
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description: |-
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The setsubtract function returns a new set containing the elements
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from the first set that are not present in the second set
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---
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# `setsubtract` Function
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-> **Note:** This page is about Terraform 0.12 and later. For Terraform 0.11 and
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earlier, see
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[0.11 Configuration Language: Interpolation Syntax](../../configuration-0-11/interpolation.html).
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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
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[relative complement](https://en.wikipedia.org/wiki/Complement_(set_theory)#Relative_complement) of the first set in the second set.
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```hcl
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setsubtract(a, b)
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```
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## Examples
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```
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> setsubtract(["a", "b", "c"], ["a", "c"])
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[
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"b",
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]
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```
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### Set Difference (Symmetric Difference)
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```
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> setunion(setsubtract(["a", "b", "c"], ["a", "c", "d"]), setsubtract(["a", "c", "d"], ["a", "b", "c"]))
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[
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"b",
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"d",
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]
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```
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## Related Functions
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* [`setintersection`](./setintersection.html) computes the _intersection_ of multiple sets
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* [`setproduct`](./setproduct.html) computes the _Cartesian product_ of multiple
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sets.
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* [`setunion`](./setunion.html) computes the _union_ of
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multiple sets.
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