It works almost exactly as the Python with statement, except you can pass more than one
variable to it.
If there's an __enter__ method it calls it, and if there's an __exit__ method it calls it
passing the eventual Exception. If any __exit__ returns true when an exception has been
raised it is ignored, if nothing returns true the exception is raised again.
If you want Python-like functionality for standard objects (for example passing an IO object to
the with and having it closed) you can require 'with/adapters', otherwise those features are
not present.
Example:
require 'with'
require 'with/adapters'
with File.new(ARGV.first, ?r) do |f|
f.read
end # this will return the contents of the passed path