I've spent many, many, many years working with YAML at $DAYJOB. YAML is just a really bad choice for configuration files that are longer than a handful of lines.
The fact that YAML encourages you to never put double-quotes around strings means that (based on my experience at $DAYJOB) one gets turbofucked by YAML mangling input by converting something that was intended to be a string into another datatype at least once a year. On top of that, the whitespace-sensitive mode makes long documents extremely easy to get lost in, and hard to figure out how to correctly edit. On top of that, the fact that the default mode of operation for every YAML parser I'm aware of emits YAML in the whitespace-sensitive mode means that approximately zero of the YAML you will ever encounter is written in the (more sane) whitespace-insensitive mode. [0]
It may be that bcl is even worse than YAML. I don't know, as I've never worked with bcl. YAML might be manna from heaven in comparison... but that doesn't mean that it's actually good.
[0] And adding to the mess is the fact that there are certain constructions (like '|') that you can't use in the whitespace-insensitive mode... so some config files simply can't be straightforwardly expressed in the other mode. "Good" job there, YAML standard authors.
The fact that YAML encourages you to never put double-quotes around strings means that (based on my experience at $DAYJOB) one gets turbofucked by YAML mangling input by converting something that was intended to be a string into another datatype at least once a year. On top of that, the whitespace-sensitive mode makes long documents extremely easy to get lost in, and hard to figure out how to correctly edit. On top of that, the fact that the default mode of operation for every YAML parser I'm aware of emits YAML in the whitespace-sensitive mode means that approximately zero of the YAML you will ever encounter is written in the (more sane) whitespace-insensitive mode. [0]
It may be that bcl is even worse than YAML. I don't know, as I've never worked with bcl. YAML might be manna from heaven in comparison... but that doesn't mean that it's actually good.
[0] And adding to the mess is the fact that there are certain constructions (like '|') that you can't use in the whitespace-insensitive mode... so some config files simply can't be straightforwardly expressed in the other mode. "Good" job there, YAML standard authors.