I have used the same "indendation" in the past. Because there are always review comments that his would be weird/confusing/unconventional I have given up on using it :(

Honestly? Give clang-format a try. There's tons of options available. Futz with them until you get a set that is to your liking, and then write them down in your repo's `.clang-format` file.

After that, the answer to "does this pull request comply with my formatting guidelines?" gets reduced to "does clang-format change this file?"

I think it's more common to put the indentation before the '#'. either way it ends up looking a little weird, but I prefer to see some visual indication of nesting.

The # doesn't need to be first on the line, looks better in my opinion.