I found those:

Underscore		. . _ _ . _
Addition		. _ . _ .
Subtraction		_ . . . . _ 
Multiplication		_ . . _
Division		_ _ _ . . .
Equal			_ . . . _
Right Parenthesis	_ . _ _ . _
Left Parenthesis	_ . _ _ .

But this isn't enough for programming, square and curly brackets, carets, ampersand, pipe, tilda... I think it's gonna be pretty challenging