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Comment by jmduke | Hacker News Reader

I love this series.

Can anyone give an example of when HAML would be used in the 'real world'? I can't imagine it filling a niche that isn't covered by any of the other templating languages: what would seem most ideal is a combination of say, Jinja and HAML.

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I'm finding that it's a lot cleaner to use with Javascript. For example, say you have an array of items and you want to create a fieldset for each item, and add an attribute of "data-id", and "data-category" to each fieldset so you can grab them with jQuery later on.

In HAML all you have to do is this...

- @items.each do |item|

  %fieldset{:data => {:id => item.id, :category => item.category}}

===

In ERB the equivalent would be...

<% @items.each do |item| %>

  <fieldset data-id="<%= item.id %>" data-category="<%= item.category %>">

  </fieldset>

<% end %>

===

It's a lot cleaner in HAML, especially extrapolated out over larger views.

Look into `tag`: http://api.rubyonrails.org/classes/ActionView/Helpers/TagHel...

ERB view:

    <%= render @items %>

items/_item.html.erb:

    <%= tag "fieldset", data: { id: item.id, category: item.category } %>

My old company used HAML exclusively for all of our RoR view code. In most general cases it makes the coding faster. THere are of course some wonky edge cases in HAML vs code style best practices.

For instance: try making an html element with a long list of attributes and see how it looks. Or worse, run a translate on a block of text while maintaining reasonable line lengths.

Good? Yes. Silver bullet html replacement? Lol.

I've always done html elements with long attribute lists, simply multiline:

    <div attr1="val1, the first one"
         attr2="val2, maybe this one is much longer"
         attr3="you see where I'm going with this"
         attr4="and so on...."
    >
        Div content goes here
    </div>

What do you mean by "run a translate" though?

I know a lot of ruby on rails developers who use HAML for their template framework instead of ERB. Some people prefer HAML's use of indentation instead of using tags to enclose everything.

I like it in my projects mostly for how clean and easy it is to read. It takes a little bit to get used to initially but it is worth it.

...and you can combine it with Sass for CSS. Sass gives you features that CSS misses like inheritence which makes your style sheets much more DRY.

BTW, both Haml and Sass go very nicely with Sinatra... ;)

SASS also works for ERB. They are independent but I do agree that they are great together.

Is there some SASS integration in HAML beyond regular HTML?

You might be interested in shpaml-jinja[0]. It extends the shpaml[1] syntax to provide jinja commands.

[0]: https://github.com/p/shpaml-jinja [1]: http://shpaml.webfactional.com/examples

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