diff --git a/ChangeLog b/ChangeLog
index 2fb6ec3b65..40ac5ffe0c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Tue Oct 11 16:38:32 2016  Tanaka Akira  <akr@fsij.org>
+
+	* lib/pp.rb (String#pretty_print): Defined to print a string as
+	  multiple lines.
+	  [ruby-core:76800] [Feature#12664] proposed by Petr Chalupa.
+
 Mon Oct 10 15:22:27 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ruby.c (open_load_file): bind the open fd to an IO instance
diff --git a/lib/pp.rb b/lib/pp.rb
index 9678774b8c..5356b7ce25 100644
--- a/lib/pp.rb
+++ b/lib/pp.rb
@@ -418,6 +418,21 @@ class Range # :nodoc:
   end
 end
 
+class String
+  def pretty_print(q)
+    lines = self.lines
+    if lines.size > 1
+      q.group(0, '', '') do
+        q.seplist(lines, lambda { q.text ' +'; q.breakable }) do |v|
+          q.pp v
+        end
+      end
+    else
+      q.text inspect
+    end
+  end
+end
+
 class File < IO # :nodoc:
   class Stat # :nodoc:
     def pretty_print(q) # :nodoc: