Ticket #478 (new enhancement)
allow comments on any line, don't require '.' for blank lines
|Reported by:||duncan||Owned by:|
It confuses people that in .cabal files, comments can only appear on lines on their own, and not at the end of other lines.
We should consider relaxing this as long as it can be done in a backwards compatible way.
The only thing to worry about is command line flags like:
If we required a space after the -- that might be sufficient. There are some tools that interpret -- on its own as an argument, but usually only as a separator between flag arguments and non-flag arguments and we do not expect those to be given in .cabal files.
We might like to allow -- within quotes eg "--" however that's also not easy because of the syntax and format of .cabal files. They have no consistent lexical syntax, each field is parsed separately. The overall structure is parsed based on layout without parsing individual fields. In particular .cabal files are not tokenised.
The second issue is easier. The original specification required that blank lines within a field include a leading . character. This applies to multi-paragraph descriptions. This syntax is totally unnecessary. The parser could cope fine without it. We should accept the convention for backwards compatibility but also allow ordinary blank lines. Multiple blank lines within a field should still be collapsed to one, and trailing blank lines within a field should be trimmed.