Appending to an existing string

Question

To append to an existing string this is what I am doing.

s = 'hello' s.gsub!(/$/, ' world'); 

Is there a better way to append to an existing string.

Before someone suggests following answer lemme show that this one does not work

s = 'hello' s.object_id s = s + ' world' s.object_id  

In the above case object_id will be different for two cases.

Answer 1

You can use << to append to a string in-place.

s = "foo" old_id = s.object_id s << "bar" s                      #=> "foobar" s.object_id == old_id  #=> true