Where is Do ... Loop without a condition documented?

Question

Apparently, one can create a Do ... Loop-Loop without a condition. The following code compiles with .NET 4.5 (fiddle) as well as with Roslyn (fiddle):

Public Sub Main()
    Do
        Console.WriteLine("Hello World")
        Exit Do
    Loop
End Sub

However, the grammar on the documentation page only offers the following two options:

Do { While | Until } condition
    [ statements ]
    [ Continue Do ]
    [ statements ]
    [ Exit Do ]
    [ statements ]
Loop
-or-
Do
    [ statements ]
    [ Continue Do ]
    [ statements ]
    [ Exit Do ]
    [ statements ]
Loop { While | Until } condition

Is this a bug in the compiler, a bug in the documentation or did I just not look hard enough?

Answer 1

When in doubt, consult the language specification, rather than the reference:

10.9.1 While...End While and Do...Loop Statements

A While or Do loop statement loops based on a Boolean expression. ... An expression may be placed after the Do keyword or after the Loop keyword, but not after both. ... It is also valid to specify no expression at all;

(My emphasis)

The language reference tries to be more straightforward but may lose essential details. The language specification should match what the compiler implements.

Answer 2

I think the key sentence in the documentation is

You can use either While or Until to specify condition, but not both.

So if you want to specify a condition you have to use either. Without a condition you do not have to specify anything.

Leaving off the condition is perfectly valid and will result in an infinite loop.