Improve syntax highlighting in README

README.md

@@ -24,51 +24,57 @@ Or install it yourself as:
 
 First, enable preloading in your `GraphQL::Schema`:
 
-    Schema = GraphQL::Schema.define do
-      use GraphQL::Batch
+```ruby
+Schema = GraphQL::Schema.define do
+  use GraphQL::Batch
 
-      enable_preloading
-    end
+  enable_preloading
+end
+```
 
 Call `preload` when defining your field:
 
-    PostType = GraphQL::ObjectType.define do
-      name 'Post'
+```ruby
+PostType = GraphQL::ObjectType.define do
+  name 'Post'
 
-      field :comments, !types[!CommentType] do
-        # Post.includes(:comments)
-        preload :comments
+  field :comments, !types[!CommentType] do
+    # Post.includes(:comments)
+    preload :comments
 
-        # Post.includes(:comments, :authors)
-        preload [:comments, :authors]
+    # Post.includes(:comments, :authors)
+    preload [:comments, :authors]
 
-        # Post.includes(:comments, authors: [:followers, :posts])
-        preload [:comments, { authors: [:followers, :posts] }]
+    # Post.includes(:comments, authors: [:followers, :posts])
+    preload [:comments, { authors: [:followers, :posts] }]
 
-        resolve ->(obj, args, ctx) { obj.comments }
-      end
-    end
+    resolve ->(obj, args, ctx) { obj.comments }
+  end
+end
+```
 
 ### `preload_scope`
 Starting with Rails 4.1, you can scope your preloaded records by passing a valid scope to [`ActiveRecord::Associations::Preloader`](https://apidock.com/rails/v4.1.8/ActiveRecord/Associations/Preloader/preload). Scoping can improve performance by reducing the number of models to be instantiated and can help with certain business goals (e.g., only returning records that have not been soft deleted).
 
 This functionality is surfaced through the `preload_scope` option:
 
-    PostType = GraphQL::ObjectType.define do
-      name 'Post'
-
-      field :comments, !types[!CommentType] do
-        preload :comments
-        preload_scope ->(args, ctx) { Comment.where(deleted_at: nil) }
-
-        # Resolves with records returned from the following query:
-        # SELECT "comments".*
-        # FROM "comments"
-        # WHERE "comments"."deleted_at" IS NULL
-        #   AND "comments"."post_id" IN (1, 2, 3)
-        resolve ->(obj, args, ctx) { obj.comments }
-      end
-    end
+```ruby
+PostType = GraphQL::ObjectType.define do
+  name 'Post'
+
+  field :comments, !types[!CommentType] do
+    preload :comments
+    preload_scope ->(args, ctx) { Comment.where(deleted_at: nil) }
+
+    # Resolves with records returned from the following query:
+    # SELECT "comments".*
+    # FROM "comments"
+    # WHERE "comments"."deleted_at" IS NULL
+    #   AND "comments"."post_id" IN (1, 2, 3)
+    resolve ->(obj, args, ctx) { obj.comments }
+  end
+end
+```
 
 ## Development