| # HCL User Functions Extension |
| |
| This HCL extension allows a calling application to support user-defined |
| functions. |
| |
| Functions are defined via a specific block type, like this: |
| |
| ```hcl |
| function "add" { |
| params = [a, b] |
| result = a + b |
| } |
| |
| function "list" { |
| params = [] |
| variadic_param = items |
| result = items |
| } |
| ``` |
| |
| The extension is implemented as a pre-processor for `cty.Body` objects. Given |
| a body that may contain functions, the `DecodeUserFunctions` function searches |
| for blocks that define functions and returns a functions map suitable for |
| inclusion in a `hcl.EvalContext`. It also returns a new `cty.Body` that |
| contains the remainder of the content from the given body, allowing for |
| further processing of remaining content. |
| |
| For more information, see [the godoc reference](https://pkg.go.dev/github.com/hashicorp/hcl/v2/ext/userfunc?tab=doc). |
