### hieradata yaml
class::myvar:
  aaa:
   - a.1
   - a.2
  bbb:
    - b.1
    - b.2
  ccc:
    - c.1
    - c.2

# initializing the class like:
$myvar = hiera_hash('class::myvar', 'dummy-value' )

## configuration.erb

myline = <%=
	@myvar.sort.each do |key, value|
		"{key} {value}"
	end
 %>


## I get:

myline = aaaa.1a.2bbbb.1b.2cccc.1c.2

## how I want

myline = aaa = a.1,a.2 ; bbb = b.1, b.2 ; ccc = c.1, c.2