Ruby templates: How to pass variables into inlined ERB?

Question

I have an ERB template inlined into Ruby code:

require \'erb\'

DATA = {
    :a => \"HELLO\",
    :b => \"WORLD\",
}

template = ERB.new <<-EOF
          


        

Answer 1

As others said, to evaluate ERB with some set of variables, you need a proper binding. There are some solutions with defining classes and methods but I think simplest and giving most control and safest is to generate a clean binding and use it to parse the ERB. Here's my take on it (ruby 2.2.x):

module B
  def self.clean_binding
    binding
  end

  def self.binding_from_hash(**vars)
    b = self.clean_binding
    vars.each do |k, v|
      b.local_variable_set k.to_sym, v
    end
    return b
  end
end
my_nice_binding = B.binding_from_hash(a: 5, **other_opts)
result = ERB.new(template).result(my_nice_binding)

I think with eval and without ** same can be made working with older ruby than 2.1