honestly that's a code smell in any data serialisation notation. if you really did have a data structure like that it would manifest in yaml as an indentation 32 space characters. If you adhere to the 78 column rule, you've squeezed most of your data to the right of almost half your screen.

Anyways, invisible syntax errors still suck. At least with json you can (eventually) figure out your braces are unbalanced. Or use a syntax highlighter to spot the problem. No syntax to highlight if you have a problem with yaml.