Is it necessary to close StringIO in ruby?

Question

Do we need to close StringIO objects after usage in Ruby in order to free resources, like we do with the real IO objects?

obj = StringIO.new \"some string\"
         


        

Answer 1

In response to the other answers here: calling close won't help you save memory.

require "stringio"
sio = StringIO.new
sio.print("A really long string")
sio.close
sio.string # => "A really long string"

"A really long string" will stay around as long as sio does, close or no close.

So why does StringIO have a close method? Duck typing. Providing close, and throwing an IOError if you try to read or write from it, ensures it acts like a real File object would. This is useful if you're using it as a mock object while unit testing.