Comment by ghostwriter
3 years ago
both symbols are delimiters, one can choose to align them together even when they are not the same character. Opening and closing braces aren't the same character either, but people have been aligning them for ages, I don't see a reason why commas, while being part of the same expression, should not follow the same principle.
For me it's not about being the same character (like you've mentioned, opening and closing braces aren't either), it's about commas and braces indicating different things in the hierarchy. Not to mention the symmetry breaking: an opening brace together with data in a line, then a lonely one at the bottom.
In a series of declarations, the lonely closing brace at the bottom can be treated as a substitute for an empty line between two entries, as it produces a similar sparse spacing.