Feature Request: Multiline condition support like in bash or python

[dylanf9797]

Hi

Currently, multiline condition is not supported and i think it can be good to have this feature.

Let's take an example

this works using Bash
test.sh

[ -f /tmp/a ] && \
  [ -f /tmp/b ] && { echo yes; } \
  || echo no

and this works in python:
test.py

t = 1
s = "hellos"

if 2 > t and \
        s == "hello":
    print("ok")
else:
    print("no")

But this not works in terraform for example:

# variables.tf

variable "hello" {
  type = string
  validation {
    condition = length(var.hello) > 0 && \
      length(var.hello) < 128

    error_message = "NO"
  }
}

[apparentlymart]

Hi @dylanf9797,

In HCL, the syntax for splitting an expression over multiple lines is to write it in some kind of brackets, which HCL then uses to understand where the multi-line expression ends.

While various kinds of bracket-shaped language features can work, the simplest answer is to use parentheses because they don't cause any other effect other than allowing the expression to wrap:

variable "hello" {
  type = string

  validation {
    condition = (
      length(var.hello) > 0 &&
      length(var.hello) < 128
    )
    error_message = "NO"
  }
}

When HCL finds the opening ( it expects the expression to continue until the matching ), ignoring any newline characters that appear in between.

I showed this as a validation condition example because that was what you asked about, but note that this is a general-purpose mechanism that works for expressions anywhere in HCL; it's not actually specific to validation conditions.

[dylanf9797]

Yes, we can use this syntax but maybe the another syntax can be added if it's considered useful for most people, otherwise, this issue can be closed.