Rails HAML conditional link_to

Question

Good day, i have this kind of code:

= link_to some_url do
  PLENTY OF MARKUP HERE

Now i need to make this link optional, so if condition is not met i need plain MARKUP to be printed, so first anti-DRY solution:

- if condition
  = link_to some_url do
    PLENTY OF MARKUP HERE
-else
  PLENTY OF MARKUP HERE REPEATED :(

Another solution if to put PLENTY OF MARKUP into partial, so i winder if where is another simple solution without partial ? I tried this one:

= link_to_if condition?, some_url do
  PLENTY OF MARKUP HERE

but unfortunately link_to_if does not work as expected here.

Answer 1

link_to_if uses the block for a different purpose compared to link_to . So it cannot do what you want.

You can define your own helper to do what you want.

If you only need to do this a few times, instead of using a custom helper, you can instead save the result of a block (the PLENTY OF MARKUP ) to a local variable, to make it easy for you to use it repeatedly. For example:

- plentyofmarkup = do
  PLENTY OF MARKUP HERE

- if condition
  = link_to (raw plentyofmarkup), some_url
- else
  = raw plentyofmarkup

Or alternatively:

= link_to_if condition, (raw plentyofmarkup), some_url

Note that the raw function is used to stop Rails from escaping the string automatically.

To define your own helper method, try:

def link_to_if_do condition, options = {}, html_options = {}
  blockresult = yield
  link_to_if condition, blockresult, options, html_options
end

Answer 2

You could always write your own conditional link helper, and put it in application_helper:

def conditional_link_to( condition, url, options = {}, html_options = {}, &block ) do
  if condition
    link_to(name, options, html_options, &block)
  else
    if block_given?
      block.arity <= 1 ? capture(name, &block) : capture(name, options, html_options, &block)
    else
      name
    end
  end
end

This is largely taken from link_to_unless , but modified to pass the block to link_to. I've not tested this, but it should be enough to give you an idea. :)