I am converting the Recycling Group Finder site from Rails 2 to Rails 3 and though it has mostly gone to plan I was temporarily held up by this error which I was getting on some pages:
The error was hard to track down as the error message wasn’t very descriptive, but in the end it turned out to be caused by a comment. I am using content_for blocks to generate sections of page content and for a long section I had added a comment to the end of the block to help be know which block was closing:
It turns out that this ‘# some_section’ comment was the problem, possibly because of the change to erubis in Rails 3. Removing the comment caused the page to start working again:
I hope this page helps short-cut the debugging for anyone else that is bitten by this issue.
Will writes 