IoResultOptional
A trait for io::Result that adds a method making it easy to tell the difference between a file not found and another error, since a common practice is to handle a file if it exists.
if let Some = open.optional?
A trait for io::Result that adds a method making it easy to tell the difference between a file not found and another error, since a common practice is to handle a file if it exists.
if let Some = open.optional?