How to conditionally display battery info

[bcc32]

I have the following snippet in my status-right:

#{?#{!=:#{battery_percentage},}, #{battery_status_bg} #{battery_remain} [#{battery_percentage}],}

The idea being that I only want to display battery info, etc. if the current machine I'm on actually has a battery. However, when I do have a battery, I get output like ~1:27 [] instead of ~1:27 [22%] as expected.

Is there a better way to detect the presence/absence of a battery rather than just testing the output of #{battery_percentage}?

[bcc32]

Appears it has to do with the fact that the variables are interpolated only once. I opened a PR.

[martinbeentjes]

Merged the PR. Thanks for your contribution!