Know your Haml comments
There are two distinct ways of commenting Haml markup: HTML and Ruby.
HTML comments
This will create an HTML comment that will be sent to the client (aka browser):
Copy/= link_to 'Example', 'www.example.com' # => <!-- = link_to 'Example', 'www.example.com' -->
Only use this variant if you need the comment to appear in the HTML.
Ruby comments
This will comment code so it will not be sent to the client:
Copy-# = link_to 'foo'
99% of the time you'll be adding notes for other developers, or disabling code sections that should not be sent to the client.
Prefer using -#
(which is actually: -
"start a Ruby block" + #
"Ruby comment").
Warning
This type of comments needs to be indented properly. If you get a syntax error (sometimes a very unhelpful one, echoing the whole file without giving a specific line number), don't forget to check the comments.
Does your version of Ruby on Rails still receive security updates?
Rails LTS provides security patches for unsupported versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2).