How to use TextField's error composable

[shalva97]

Decided to use the TextField's error argument. But the red icon is always visible

How do I use it? my first try was this

TextField(value = server,
    modifier = Modifier.fillMaxWidth(),
    error = {
        if (errors.value is Errors.BadServer) {
            Text(text = "Can not connect to this server")
        }
    },)

That did not work because it checks if the argument is null and then displays red icon. My second try was:

val error = @Composable { if (errors.value is Errors.BadServer) {
    Text(text = "Can not connect to this server")
} else null }

TextField(value = server,
    modifier = Modifier.fillMaxWidth(),
    error = error) // here I get error "The feature "unit conversion" is disabled"

But there I get compilation error. Of course I could duplicate it and wrap whole TextField in if statement, but this feels wrong (lots of arguments will be duplicated). So how can I use it?

[hrach]

TextField(
    value = server,
    modifier = Modifier.fillMaxWidth(),
    error = if (errors.value is Errors.BadServer) {
        @Composable { Text(text = "Can not connect to this server") }
    } else {
        null
    },
)