Hey @alixander , there's another way to solve this problem i.e. by validating colors during rendering instead of at compile time.
Approach 1 (Current PR):

• It validates at compile time (faster error feedback).
• Code changes are limited to gradient.go.
  I know this approach also has cons, like we are parsing gradients twice here(once during compilation & secondly during rendering) & as you might said ValidColor check might not be as expected.

Approach 2 Closed PR(#2491):

• It validates colors while rendering.
• Code changes in multiple files + adding error returns in multiple func s.

I went with the first approach since it fails faster and keeps changes contained, but I’d love your thoughts on which one you prefer.

I meant if you just add your current check to here: https://github.com/terrastruct/d2/blob/master/lib/color/color.go#L514 , it's cleaner

I meant if you just add your current check to here: https://github.com/terrastruct/d2/blob/master/lib/color/color.go#L514 , it's cleaner

Ah okay, that makes sense.