Hotfix to prevent frozen string with 240

lib/marc_source.rb

@@ -69,33 +69,33 @@ def get_std_title
     # Quartets
     node = first_occurance("240", "a")
     standard_title = node.content.truncate(50) if node && node.content
-    standard_title.strip! if standard_title
+    standard_title = standard_title.strip if standard_title
 
     # try to get the description (240 m)
     # vl (2), vla, vlc
     node = first_occurance("240", "m")
     scoring = node.content.truncate(50) if node && node.content
-    scoring.strip! if scoring
+    scoring = scoring.strip if scoring
 
     node = first_occurance("240", "k")
     extract = node.content.truncate(50) if node && node.content
-    extract.strip! if extract
+    extract = extract.strip if extract
 
     node = first_occurance("240", "o")
     arr = node.content.truncate(50) if node && node.content
-    arr.strip! if arr
+    arr = arr.strip if arr
 
     node = first_occurance("383", "b")
     opus = node.content.truncate(50) if node && node.content
-    opus.strip! if opus
+    opus = opus.strip if opus
 
     node = first_occurance("690", "a")
     cat_a = node.content.truncate(50) if node && node.content
-    cat_a.strip! if cat_a
+    cat_a = cat_a.strip if cat_a
 
     node = first_occurance("690", "n")
     cat_n = node.content.truncate(50) if node && node.content
-    cat_n.strip! if cat_n
+    cat_n = cat_n.strip if cat_n
 
     cat_no = "#{cat_a} #{cat_n}".strip
     cat_no = nil if cat_no.empty? # For the join only nil is skipped