generator: can't use iterator value in for loop

[adonespitogo]

I can't use the i variable in this for loop example:

for i, nav := range navs {
  if nav.Active {
    <a id={ navId(i) } href="{ nav.Url }">{ nav.Text }</a>
  }
}

func navId(i int) {
  return fmt.Sprintf("navid-%d", i)
}

Error:

i declared and not used

[a-h]

Oh, that's not right. I was surprised that this isn't covered in the test suites, but all of the tests use the empty value (_). I'll sort that too.

I suspect this issue was introduced when go expressions started being formatted, and the parser errors propagated.

I won't be able to fix it until next weekend though.

In the meantime, the classic 3 part for loop will work (for i := 0; i < len(z); i++), albeit it's less ergonomic.

I think the fix will likely be to ignore unused variable errors during formatting operations, and leave any unused variable issues to be discovered in the generated output, but I'll have to look into it more.

[adonespitogo]

Thank you, great project by the way. I'll use the classic for loop for now.

[joerdav]

Hi @adonespitogo I'm taking a look at this. What version of templ are you using please?

[joerdav]

Second, what command are you running to see this error? Or is it in the editor?

[adonespitogo]

Hi @joerdav

Hi @adonespitogo I'm taking a look at this. What version of templ are you using please?

v0.2.707

Second, what command are you running to see this error? Or is it in the editor?

cd templates && templ generate

[joerdav]

I'm struggling to reproduce this, your original code is not valid templ so I couldn't just copy it into a file. I changed it into a valid templ file and couldn't get it to error:

package adon

templ t() {
	for i, nav := range navs {
		if nav.Active {
			<a id={ navId(i) } href="{ nav.Url }">{ nav.Text }</a>
		}
	}
}

func navId(i int) {
	return fmt.Sprintf("navid-%d", i)
}

Please can you consider creating a minimal reproducible example, either as a github repo or a single templ file that I can copy?

[adonespitogo]

Hi @joerdav

I can no longer reproduce this issue. Perhaps it was a mistake on my part, a lot has changed in my code since then. Sorry for bringing this up. Feel free to close this issue.

[joerdav]

No problem, thanks for coming back to update!