---
title: 'Fashion Runway: ERb vs. Haml'
teaser:
tags: web,ruby,rails
author: Dan Croak
published_on: 2009-08-05
---
With Rails 3 around the corner, choosing a templating framework (and testing
frameworks and ORMs) will be a decision Rails developers can make on even
ground. [ERb](http://www.ruby-doc.org/stdlib/libdoc/erb/rdoc/classes/ERB.html)
and [Haml](http://haml.hamptoncatlin.com) will be equally supported in places
such as generators.
So how do we choose?
## Looks
[A](http://twitter.com/davidalln/statuses/1499062567)
[lot](http://twitter.com/lucaspiller/statuses/1489628312) of
[people](http://twitter.com/haruki_zaemon/statuses/1481876183)
[think](http://twitter.com/chriseppstein/statuses/1478941207)
[Haml](http://twitter.com/tvars/statuses/1482314227) is
[great-looking](http://twitter.com/timcase/statuses/1477943964).
It's true. Haml looks very clean in the examples. I think the template code in
[Boston.rb](http://bostonrb.org) is quite beautiful:
```haml
#events
.ribbon
.row
.crud
%p= link_to 'New event', new_event_path
%h2 Recurring Events
- @recurring_events.each do |event|
.quarter>
%p.date
%
= event.date.to_s(:fancy_date)
%span= event.date.to_s(:time)
%h3= link_to h(event.title), event
%p= event.cached_description_html
```
Very readable. All those noisy `<% end %>`s and closing HTML tags are gone.
## ERb is beautiful, too
ERb, I imagine you must take all this Haml attention personally. Don't feel
down. Your `` is a wonderland.
For example, when I want to **go vertical** when I want to, such as in this
[Formtastic](http://github.com/justinfrench/formtastic) example from one of our
apps:
```erb
<%= form.input :logo,
:input_html => { :class => "upload_field",
:style => "width: 340px;" },
:label => 'Logo',
:size => '30' %>
```
Or this example of a typical Clearance sign up form:
## Sign In
```erb
<% semantic_form_for :session, :url => session_path do |form| %>
<% form.inputs do %>
<%= form.input :email %>
<%= form.input :password, :as => :password %>
<%= form.input :remember_me, :as => :boolean, :required => false %>
<% end %>
<% form.buttons do %>
<%= form.commit_button "Sign In" %>
<% end %>
<% end %>
```
This style is in line with a few of thoughtbot's internal coding standards:
* indent two spaces regardless of HTML or ERb tags
* align hash keys and hash rockets when going vertical
The first standard is exactly the same as Haml but the second is intentionally
awkward in Haml using the pipe character. Hamlistas will say: **move it into a
helper**.
Good point. Then you can **go vertical** in normal Ruby code.
## Is beauty only skin deep
The argument for either framework on looks alone is unfortunately steeped in
personal preference. Let's go deeper.
## One fewer thing to learn
I worked on a Rails project with a PHP developer. I wanted her to learn Ruby, testing with
Shoulda and Factory Bot, git, REST... Haml was a lower priority. ERb and
immediately felt familiar to her.
Lesson: ERb's interpolated tags are familiar for ASP, PHP, and JSP developers.
Yet the same one fewer thing to learn argument can be made for Haml. Look at
that Boston.rb example again. Now see how our JQuery code deals with `.crud`
inside `#events`:
```javascript
jQuery(document).ready(function($) {
$('#events, #jobs, #projects, #presentations, #companies, #apps, #show, #edit').hover(
function() {
$(this).find('.crud').show();
},
function() {
$(this).find('.crud').hide();
}
);
});
```
Lesson: Haml's re-use of CSS
selectors are familiar for CSS and
Javascript developers.
## Active development
Haml is under active development. For example, the Haml team [recently responded
to newer competitor, Less](http://nex-3.com/posts/83-sass-and-less) by altering
Sass to become a superset of CSS. New ideas and features are being shared and
improved upon.
ERb isn't capturing the imaginations of the open source community right now, but
is also older and **stable**. It is working software that you can wrap around
yourself like a security blanket.
## The only thing that matters: institutional standardization
thoughtbot standardized on ERb. Hoptoad was on Haml for a long time but we
converted it to Erb.
[Hashrocket](http://blog.obiefernandez.com/content/2008/01/are-you-using-h.html)
announced they standardized on Haml.
Both are examples of companies that work on a lot of apps. I believe the gains
from **institutional standardization**, such as code re-use and developers
mastering a common set of tools, outweigh any other pro or con and likely leads
to cost savings.
Visit our [Open Source page](https://thoughtbot.com/open-source) to learn more about our team's contributions.