Rid off duplicated to_json #72

Author: Seiichi Yonezawa

databases/mongo.md

@@ -70,7 +70,7 @@ end
 # find a document by its ID
 get '/document/:id/?' do
   content_type :json
-  document_by_id(params[:id]).to_json
+  document_by_id(params[:id])
 end
 ```
 
@@ -82,7 +82,7 @@ end
 post '/new_document/?' do
   content_type :json
   new_id = settings.mongo_db['test'].insert params
-  document_by_id(new_id).to_json
+  document_by_id(new_id)
 end
 ```
 
@@ -95,7 +95,7 @@ put '/update/:id/?' do
   content_type :json
   id = object_id(params[:id])
   settings.mongo_db['test'].update({:_id => id}, params)
-  document_by_id(id).to_json
+  document_by_id(id)
 end
 
 # update the document specified by :id, setting just its
@@ -106,8 +106,8 @@ put '/update_name/:id/?' do
   id   = object_id(params[:id])
   name = params[:name]
   settings.mongo_db['test'].
-    update(:_id => id, {"$set" => {:name => name}})
-  document_by_id(id).to_json
+    update({:_id => id}, {"$set" => {:name => name}})
+  document_by_id(id)
 end
 ```