Question

I’m printing a list from an array object and when it’s done going through all the items in the array, it prints the word “true” in the HTML.

The code looks like this:

%ul 
  = for i in users
    %li
      = i.username

This prints:

username1
username2
username3
true

which looks like this in the html output:

<ul>
  <li>username1</li>
  <li>username2</li>
  <li>username3</li>
  true
</ul>

Why is that true getting printed and how do I get rid of it?

Answer 1

Your problem is that you are using = for the loop, which causes the result of the expression to be output. When you want to run Ruby code but not have the value emitted into the output, use - instead:

%ul 
  - for i in users
    %li
      = i.username

This can be written more simply as:

%ul 
  - for i in users
    %li= i.username

Proof:

C:\>haml
- users = %w[user1 user2 user3]
%ul
  - for name in users
    %li= name
^Z
<ul>
  <li>user1</li>
  <li>user2</li>
  <li>user3</li>
</ul>

---

As an aside, I personally find this usage of for in Ruby abhorrent. Instead I personally recommend:

%ul 
  - users.each do |user|
    %li= user.username