Incorrect $ parsing as string element

[doctornkz]

How repoduce:
Go to https://play.golang.org/
Put that code there:

package main
import (
	"fmt"
	"github.com/hashicorp/hcl2/hclwrite"
	"github.com/zclconf/go-cty/cty"
)
func main() {
	f := hclwrite.NewEmptyFile()
	rootBody := f.Body()
	rootBody.SetAttributeValue("hello", cty.StringVal("${world}"))
	fmt.Printf("%s", f.Bytes())
}

Receive:

hello = "$${world}"

Expected:
hello = "${world}"

I was trying a couple ways to escape that, but it doesn't work.

[doctornkz]

I found the tricky solution. If I use cty.StringVal("$${world}") I am receiving hello = "$$${world}" and doubled $$ compensate each other and it works like one $. But I think it's not good way to fix.

[apparentlymart]

Hi @doctornkz,

What you are seeing here seems to be an HCL behavior, not a cty behavior. With that said, I believe it's working as intended because it's escaping the ${ sequence in your literal string so that the HCL parser would then see it as a literal ${ rather than the beginning of an interpolation sequence. If you'd like to discuss this more, please open an issue in the HCL repository.

[doctornkz]

I solved problem with hcl.Traversal() .Now, I can create templated config file. Ugly, but works good for me.

[marcsauter]

@doctornkz do you have an example of your solution?

[doctornkz]

@marcsauter take a look here: https://github.com/doctornkz/signalfx2terraform/blob/master/builder/dashboard.go#L79-L84
it gives me possibility generate that example:

  chart {                  
    chart_id = "${signalfx_time_chart.sfx-XXXXXX.id}"
    column   = 0    
    row      = 1
    width    = 6
    height   = 1                                                      
  }

with ${} inside the structure

[marcsauter]

Thank you so much, that solves out problem.