When is File.join useful?

Question

From reading the documentation, it's apparent that File.join joins the given parameters with the / character.
When is using this, as opposed to filenames.join('/'), beneficial?

Answer 1

There is another, subtle difference:

File.join('foo','bar') #=> "foo/bar" ['foo','bar'].join('/') #=> "foo/bar" 

But, if you pass an argument already ending with / (which is quite often when working with paths), you won't have two slashes in the result:

File.join('foo/','bar') #=> "foo/bar" ['foo/','bar'].join('/') #=> "foo//bar" 

Answer 2

It will use File::SEPARATOR, which in theory need not be /.