[\#‑\*]

All of the characters found between # and * in the ASCII collation sequence.

[A0\[\]/u]

The letter a, forced to uppercase, the digit 0 and brackets.

[#abc]

Any character acceptable in your installation as a digit and the letters a, b, and c

[&\*\$]

Any character acceptable in your system as the first character in a name and the characters * and $.

[abc//a]

The characters a, b, and c, with a default of a if the user fails to make an entry or enters a space.