Add Stack Heredocs In A Method Call as a Ruby TIL

ruby/stack-heredocs-in-a-method-call.md

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+# Stack Heredocs In A Method Call
+
+When you put a heredoc directly in a method call as an argument, it is only the
+opening identifier that goes in the argument list.
+
+That looks like this:
+
+```ruby
+execute_in_transaction(<<~SQL)
+  update reading_statuses
+  set status = 'abandoned'
+  where started_at < (now() - '2 years'::interval)
+    and finished_at is null;
+SQL
+```
+
+You might imagine then that we can put multiple heredocs in a method call. That
+leads to [_stacked
+heredocs_](https://www.visualmode.dev/ruby-operators/heredoc#stacked-heredocs).
+
+```ruby
+execute_in_transaction(<<~SQL1, <<~SQL2, <<~SQL3)
+  update reading_statuses
+  set status = 'abandoned'
+  where started_at < (now() - '2 years'::interval)
+    and finished_at is null;
+SQL1
+  insert into activity_log (name, description)
+  values ('abandon_books', 'Mark unread books as abandoned');
+SQL2
+  delete from background_jobs
+  where id = #{job_id}; -- better to sanitize values like this
+SQL3
+```
+
+Notice we terminate the body of each heredoc with its closing identifier and
+immediately begin the body of the next one.