57 lines
1.9 KiB
Plaintext
57 lines
1.9 KiB
Plaintext
---
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layout: docs
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page_title: Local Values - HCL Configuration Language
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description: >-
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Local values assign a name to an expression that can then be used multiple
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times within a folder.
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---
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# Local Values
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Local values assign a name to an expression, that can then be used multiple
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times within a folder.
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If [variables](/docs/job-specification/hcl2/variables) are analogous to
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function arguments then _local values_ are comparable to a function's local
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variables.
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## Examples
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Local values are defined in `locals` blocks:
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```hcl
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# A computed default name prefix
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locals {
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default_name_prefix = "${var.project_name}-web"
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name_prefix = "${var.name_prefix != "" ? var.name_prefix : local.default_name_prefix}"
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# unlike variables, locals don't have type constraints, so if you use
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# functions that take maps but not objects, you may need to convert them
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number_of_ports = length(convert({"www" = "80"}, map(string)))
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}
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# Local values can be interpolated elsewhere using the "local." prefix.
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job "example_loadbalancer" {
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name = "${local.name_prefix}_loadbalancer"
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# ...
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}
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```
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## Description
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The `locals` block defines one or more local variables.
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The names given for the items in the `locals` block must be unique. The given
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value can be any expression that is valid within the current file.
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The expression of a local value can refer to other locals, but reference cycles
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are not allowed. That is, a local cannot refer to itself or to a variable that
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refers (directly or indirectly) back to it.
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It's recommended to group together logically-related local values into a single
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block, particularly if they depend on each other. This will help the reader
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understand the relationships between variables. Conversely, prefer to define
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_unrelated_ local values in _separate_ blocks, and consider annotating each
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block with a comment describing any context common to all of the enclosed
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locals.
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