relevant quote from the linked docs: > `unsafeInterleaveIO` allows an IO computation to be deferred lazily. When passed a value of type IO a, the IO will only

relevant quote from the linked docs: > `unsafeInterleaveIO` allows an IO computation to be deferred lazily. When passed a value of type IO a, the IO will only be performed when the value of the a is demanded. This is used to implement lazy file reading, see `hGetContents`.