What does "(.1..10.)" mean in an array declaration?

Question

Nick Hodges mentioned in an article that the following still compiles:

var
  WeirdLookingArray: array(.1..10.) of string;

What is the meaning of "." in beginning and end?

Answer 1

(. and .) are alternative ways of writing [ and ], respectively.

You can also write (* and *) instead of { and }.

Answer 2

These are called digraphs. Has been described in documentation too.