Question

This code in helper:

def dgtags
    if params[:controller]=='my_controller'
      javascript_include_tag('dygraph-combined.js') <<
          tag(:meta, :http_equiv => 'X-UA-Compatible', :content => 'IE=EmulateIE7; IE=EmulateIE9') <<
          '<!--[if IE]>'.html_safe <<
          javascript_include_tag('excanvas.compiled.js') <<
          '<![endif]-->'.html_safe
    end
end

produces following output:

<script src="/javascripts/dygraph-combined.js?1338036501" type="text/javascript"></script><meta content="IE=EmulateIE7; IE=EmulateIE9" http_equiv="X-UA-Compatible" /><!--[if IE]><script src="/javascripts/excanvas.compiled.js?1237712986" type="text/javascript"></script><![endif]-->

How to insert line breaks between tags? Like this:

<script src="/javascripts/dygraph-combined.js?1338036501" type="text/javascript"></script>
<meta content="IE=EmulateIE7; IE=EmulateIE9" http_equiv="X-UA-Compatible" />
<!--[if IE]><script src="/javascripts/excanvas.compiled.js?1237712986" type="text/javascript"></script><![endif]-->

The ‘\n’ or ‘\n’.html_safe does not help – it produces literally \n.

Answer 1

You have to use double quotes "

Use "\n" not '\n'

You can get more detailed information here: http://en.wikibooks.org/wiki/Ruby_Programming/Strings

I have changed your code a bit. Better approach is to join all elements using "\n". Also you can use controller_name instead of params[:controller].

def dgtags
    if controller_name == 'my_controller'
      [ javascript_include_tag('dygraph-combined.js'),
        tag(:meta, :http_equiv => 'X-UA-Compatible', :content => 'IE=EmulateIE7; IE=EmulateIE9'),
        '<!--[if IE]>',
        javascript_include_tag('excanvas.compiled.js'),
        '<![endif]-->'].join("\n").html_safe
    end
end