diff --git a/lib/puppet/pops/adapters.rb b/lib/puppet/pops/adapters.rb
index 294639172..47add77ea 100644
--- a/lib/puppet/pops/adapters.rb
+++ b/lib/puppet/pops/adapters.rb
@@ -1,108 +1,108 @@
 # The Adapters module contains adapters for Documentation, Origin, SourcePosition, and Loader.
 #
 module Puppet::Pops::Adapters
   # A documentation adapter adapts an object with a documentation string.
   # (The intended use is for a source text parser to extract documentation and store this
   # in DocumentationAdapter instances).
   #
   class DocumentationAdapter < Puppet::Pops::Adaptable::Adapter
     # @return [String] The documentation associated with an object
     attr_accessor :documentation
   end
 
   # A SourcePosAdapter holds a reference to  a *Positioned* object (object that has offset and length).
   # This somewhat complex structure makes it possible to correctly refer to a source position
   # in source that is embedded in some resource; a parser only sees the embedded snippet of source text
   # and does not know where it was embedded. It also enables lazy evaluation of source positions (they are
   # rarely needed - typically just when there is an error to report.
   #
   # @note It is relatively expensive to compute line and position on line - it is not something that
   #   should be done for every token or model object.
   #
   # @see Puppet::Pops::Utils#find_adapter, Puppet::Pops::Utils#find_closest_positioned
   #
   class SourcePosAdapter < Puppet::Pops::Adaptable::Adapter
     attr_accessor :locator
 
     def self.create_adapter(o)
       new(o)
     end
 
     def initialize(o)
       @adapted = o
     end
 
     def locator
       # The locator is always the parent locator, all positioned objects are positioned within their
       # parent. If a positioned object also has a locator that locator is for its children!
       #
       @locator ||= find_locator(@adapted.eContainer)
     end
 
     def find_locator(o)
       if o.nil?
         raise ArgumentError, "InternalError: SourcePosAdapter for something that has no locator among parents"
       end
       case
       when o.is_a?(Puppet::Pops::Model::Program)
         return o.locator
       # TODO_HEREDOC use case of SubLocator instead
       when o.is_a?(Puppet::Pops::Model::SubLocatedExpression) && !(found_locator = o.locator).nil?
         return found_locator
       when adapter = self.class.get(o)
         return adapter.locator
       else
         find_locator(o.eContainer)
       end
     end
     private :find_locator
 
     def offset
       @adapted.offset
     end
 
     def length
       @adapted.length
     end
 
     # Produces the line number for the given offset.
     # @note This is an expensive operation
     #
     def line
-      locator.line_for_offset(offset)
+      (@locator ||= find_locator(@adapted.eContainer)).line_for_offset(offset)
     end
 
     # Produces the position on the line of the given offset.
     # @note This is an expensive operation
     #
     def pos
       locator.pos_on_line(offset)
     end
 
     # Extracts the text represented by this source position (the string is obtained from the locator)
     def extract_text
       locator.string.slice(offset, length)
     end
 
     # Produces an URI with path?line=n&pos=n. If origin is unknown the URI is string:?line=n&pos=n
     def to_uri
       f = locator.file
       f = 'string:' if f.nil? || f.empty?
       URI("#{f}?line=#{line.to_s}&pos=#{pos.to_s}")
     end
   end
 
   # A LoaderAdapter adapts an object with a {Puppet::Pops::Loader}. This is used to make further loading from the
   # perspective of the adapted object take place in the perspective of this Loader.
   #
   # It is typically enough to adapt the root of a model as a search is made towards the root of the model
   # until a loader is found, but there is no harm in duplicating this information provided a contained
   # object is adapted with the correct loader.
   #
   # @see Puppet::Pops::Utils#find_adapter
   #
   class LoaderAdapter < Puppet::Pops::Adaptable::Adapter
     # @return [Puppet::Pops::Loader::Loader] the loader
     attr_accessor :loader
   end
 end