erb how to loop on array

Question

I can't simply loop on an array with ruby erb template system...

here is my template:

<% ['foo', 'bar'].each do |val| -%>
<%= val %>
<% end -%>

Here is the command line and the result

erb test.erb
/usr/share/rvm/rubies/ruby-2.4.1/lib/ruby/2.4.0/erb.rb:896:in `eval': test.erb:1: syntax error, unexpected ';' (SyntaxError)
'foo', 'bar'].each do |val| -; _erbout.concat "\n"
                              ^
test.erb:3: syntax error, unexpected ';'
;  end -; _erbout.concat "\n"
         ^
        from /usr/share/rvm/rubies/ruby-2.4.1/lib/ruby/2.4.0/erb.rb:896:in `result'
        from /usr/share/rvm/rubies/ruby-2.4.1/lib/ruby/2.4.0/erb.rb:878:in `run'
        from /usr/share/rvm/rubies/ruby-2.4.1/bin/erb:149:in `run'
        from /usr/share/rvm/rubies/ruby-2.4.1/bin/erb:170:in `<main>'

What is wrong with this really simple example?

Disclaimer: I am a ruby and erb noob ^^

The thing that error message is also pretty unclear. To me, it should have told you unexpected '-' — committedandroider
– committedandroider, Commented Oct 7, 2019 at 16:01

Oli Crt · Accepted Answer · 2023-09-22 13:27:23Z

6

You're not supposed to have those "-" at the end before the "%".

<% ['foo', 'bar'].each do |val| %>
    <%= val %>
<% end %>

This should work.

edited Sep 22, 2023 at 13:27

answered Feb 14, 2018 at 10:11

Oli Crt

1,2031 gold badge12 silver badges15 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

nemenems Over a year ago

indeed it works! but I don't understand, the "-"is here to not add a newline char (from my understanding). I saw a lot of examples with this syntax. Why am i not supposed to use the "-" here ?

Oli Crt Over a year ago

@nemenems Seems like you need to enable it doing ERB.new(template, nil, '-'), see this post for more info stackoverflow.com/questions/4632879/…

nemenems Over a year ago

perfect! you rocks!

Stefan · Accepted Answer · 2018-02-14 10:34:34Z

3

You have to set trim mode to -:

$ erb -T - test.erb
foo
bar

From the man page:

-T mode   Specifies trim mode (default 0). mode can be one of
          0   EOL remains after the embedded ruby script is evaluated.
          1   EOL is removed if the line ends with %>.
          2   EOL is removed if the line starts with <% and ends with %>.
          -   EOL is removed if the line ends with -%>. And leading whitespaces
              are removed if the erb directive starts with <%-.

edited Feb 14, 2018 at 10:34

answered Feb 14, 2018 at 10:13

Stefan

115k14 gold badges157 silver badges234 bronze badges

Collectives™ on Stack Overflow

erb how to loop on array

2 Answers 2

3 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related