When I used <% and # with a space between them, it breaks other HTML elements around the code in Rails version 2.3. However, you should be able to use <% # (without a space), and this is the correct way to have comments in erb, check this: http://en.wikipedia.org/wiki/ERuby
Besides
"Aaah. Got this, I tried <% = #TODO ...%>. Thank you very much. Can you give an idea of โโthe value of" = "(ie <% = ...%> vs. <%. ..%>? - Derek Hill June 30 at 11:25 pm "
In response to the above question:
The content between <% = ..%> is interpreted and executed as Ruby code, and the result is converted to a string and printed on the output instead of <% = ..%>. While the content between <% ..%> is interpreted and executed as Ruby code with no result displayed on the output.
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