General rule for variable, label, subroutine names are:

• starts with “_” or alphabet character.
• followed by “_”, alphabet or number.

But I found some multi-byte characters can be used for these names in Small Basic.  There are not official documents about it.

So following is my conjecture about which character can be used for variable, label and subroutine names:

• Double byte characters can be used like alphabet.
• But no double byte symbol can be used.

Sample code is here.

I think this is useful for following cases:

• to write names in your local languages. ex. なまえ = “のんき”
• to use Greek alphabet in equations. ex. x = r * Math.Cos(θ)

See Also

• Small Basic: Character Set – Unicode (TechNet Wiki)