This version only supports the R 'times' and E instructions for repetition, which cannot be nested.
Instruction description:
C FLOAT (C is a char, FLOAT is a float)
Combinations
F distance (move turtle forward by 'distance', print line if pencil is down)
T angle (turn turtle by 'angle' (positive angle counterclockwise))
U (move pencil up)
D (move pencil down)
R repetition (repeat following operation until E operator or end of file 'repetition' times, it is not possible to nest these)
E (marks end of repetition block)
{ (remember coordinates and angle)
} (goto remembered coordinates and angle)