Chapter 12 - Haml

Question 1

Create an Element

Answer 1

To create an HTML element in Haml, one simply needs to prefix the percent character (%) to an element name. The element name can be any string, allowing you to use newly added HTML5 elements, such as header.

%header content

content header >

Question 2

Attributes

Answer 2

Attributes in Haml are defined using two styles. The first style involves defining attributes between curly braces ({}).

%a{ title: @article.title, href: article_path(@ article) } Title

%a( title=@article.title href = article_path(@article)) Title

Question 3

Haml Comment

Answer 3

-#

Question 4

Evaluating Ruby code

Answer 4

Somewhat similar to ERb, using the equals character (=) results in Haml evaluating Ruby code following the character and outputting the result into the document.

%p = %w( foo bar). join(‘ ‘)

HTML foo bar p >

Alternatively, using the hyphen character (-) evaluates Ruby code but doesn’t insert its output into the resulting document. This is commonly used in combination with if/ else statements and loops.

• if flash.notice.
  .notice= flash.notice

Question 5

Interpolation

Answer 5

Ruby code can be interpolated in two ways in Haml: inline with plain text using #{} or using string interpolation in combination with =.

%p By: #{ post.author_name}

%p = “By: #{ post.author_name}”