Scratch_EBNF.ebnf

ask about set rotatio block 

(Backdrop) 
BACKDROP = VAR; 
(Sprite Definitions) 
SPRITES = SPRITE {"," SPRITE}; 
SPRITE = "(", SPRITE_NAME, "),", "(", SPRITE_VARIABLES, "),",
    "(", SPRITE_LISTS, "),","(", SPRITE_BROADCASTS, "),",
    "(", SPRITE_BLOCKS, "),","(", SPRITE_COMMENTS, "),",
    "(", SPRITE_CURR_COSTUME, "),","(", SPRITE_COSTUMES, "),",;
SPRITE_NAME = VAR; 
SPRITE_VARIABLES = VAR {", ", VAR}; 
SPRITE_LISTS = VAR {", ", VAR}; 
SPRITE_BROADCASTS = VAR {", ", VAR};
SPRITE_BLOCKS = BLOCK_TYPE {", ", BLOCK_TYPE};
SPRITE_COMMENTS = = string {", ", string};
SPRITE_CURR_COSTUME = COSTUME;
SPRITE_COSTUMES = COSTUME {", ", COSTUME};
COSTUME = "costume: ", VAR, "; filepath: ", string, "; "; 

(Block Hierarchy) 
BLOCK_TYPE = 
MOTION_BLOCK
| LOOKS_BLOCK
| SOUND_BLOCK
| EVENT_BLOCK
| CONTROL_BLOCK
| SENSING_BLOCK 
| OPERATORS_BLOCK
| MY_BLOCKS

MOTION_BLOCK = 
MOVE_BLOCK 
| TURN_CW_BLOCK
| TURN_CCW_BLOCK
| GO_TO_VAR_BLOCK 
| GO_TO_VAL_BLOCK
| GLIDE_VAR_BLOCK 
| GLIDE_COORD_BLOCK 
| POINT_DIRECTION_BLOCK 
| POINT_VAR_BLOCK 
| CHANGE_X_BLOCK 
| SET_X_BLOCK 
| CHANGE_Y_BLOCK 
| SET_Y_BLOCK 
| BOUNCE_EDGE_BLOCK
| SET_ROTATION_BLOCK

LOOKS_BLOCK = 
SAY_FOR_BLOCK
| SAY_BLOCK
| THINK_FOR_BLOCK
| THINK_BLOCK
| SWITCH_COSTUME_BLOCK
| NEXT_COSTUME_BLOCK
| SWITCH_BACKDROP_BLOCK
| NEXT_BACKDROP_BLOCK
| CHANGE_SIZE_BLOCK
| SET_SIZE_BLOCK
| CHANGE_VAR_BY_BLOCK
| SET_VAR_TO_BLOCK
| CLEAR_GRAPHICS_BLOCK
| SHOW_BLOCK
| HIDE_BLOCK 
| GO_TO_LAYER_BLOCK
| GO_TO_NTH_BLOCK

SOUND_BLOCK =
PLAY_UNTIL_BLOCK
| START_SOUND_BLOCK
| STOP_SOUNDS_BLOCK
| CHANGE_VAR_BY_BLOCK
| SET_VAR_BY_BLOCK
| CLEAR_SOUNDS_BLOCK
| CHANGE_VOLUME_BLOCK
| SET_VOLUME_BLOCK

EVENT_BLOCK = 
GREEN_FLAG_BLOCK
| KEY_PRESSED_BLOCK
| SPRITE_CLICKED_BLOCK
| BACKDROP_SWITCHED_BLOCK
| WHEN_GREATER_BLOCK
| WHEN_RECEIVE_BLOCK
| BROADCAST_MESSAGE_BLOCK
| BROADCAST_THEN_WAIT_BLOCK

CONTROL_BLOCK = 
Wait Block 
| REPEAT_BLOCK
| FOREVER_BLOCK
| IF_BLOCK
| IF_ELSE_BLOCK
| WAIT_UNTIL_BLOCK 
| REPEAT_UNTIL_BLOCK 
| STOP_VAR_BLOCK
| WHEN_START_CLONE_BLOCK
| CREATE_CLONE_BLOCK
| DELETE_CLONE_BLOCK

SENSING_BLOCK =
TOUCHING_VAR_OPERATOR
| TOUCHING_COLOR_OPERATOR
| COLORS_TOUCHING_OPERATOR
| ASK_WAIT_BLOCK
| KEY_PRESSED_OPERATOR
| MOUSE_CLICKED_OPERATOR
| SET_DRAG_VAR_BLOCK
| RESET_TIMER_BLOCK

OPERATORS_BLOCK = 
PLUS_OPERATOR
| MINUS_OPEATOR 
| MULTIPLY_OPERATOR 
| DIVIDE_OPERATOR
| RANDOM_OPERATOR
| GREATER_THAN_BLOCK
| LESS_THAN_OPERATOR 
| EQUALS_OPERATOR
| AND_OPERATOR
| OR_OPERATOR
| NOT_OPERATOR
| JOIN_BLOCK
| LETTER_BLOCK
| LENGTH_BLOCK
| CONTAINS_OPERATOR
| MOD_BLOCK
| ROUND_BLOCK
| FUNCTION_BLOCK

MY_BLOCKS = 
SET_VAR_BLOCK  
| CHANGE_VAR_BLOCK
| SHOW_VAR_BLOCK 
| HIDE_VAR_BLOCK 

(Block Definitions) 
MOVE_BLOCK = "move ", N_VAL, " steps";
TURN_CW_BLOCK = "turn clockwise ", N_VAL, " degrees"; 
TURN_CCW_BLOCK = "turn counter-clockwise ", N_VAL, " degrees";
GO_TO_VAR_BLOCK = "go to ", VAR;
GO_TO_VAL_BLOCK = "go to x:", N_VAL, " y:", N_VAL;
GLIDE_VAR_BLOCK = "glide ", N_VAL, " secs to ", VAR;
GLIDE_COORD_BLOCK = "glide ", N_VAL, " secs to x: ", N_VAL, " y: ", N_VAL;
POINT_DIRECTION_BLOCK = "point in direction ", N_VAL; 
POINT_VAR_BLOCK = "point towards ", VAR; 
CHANGE_X_BLOCK = "change x by ", N_VAL; 
SET_X_BLOCK = "set x to ", N_VAL; 
CHANGE_Y_BLOCK = "change y by ", N_VAL; 
SET_Y_BLOCK = "set y to ", N_VAL; 
BOUNCE_EDGE_BLOCK = "if on edge, bounce"; 
SET_ROTATION_BLOCK = "set rotation style ", ROT_STYLE;  

SAY_FOR_BLOCK = "say ", S_VAL, " for ", N_VAL, " seconds "; 
SAY_BLOCK = "say ", S_VAL; 
THINK_FOR_BLOCK = "think ", S_VAL, " for ", N_VAL, " seconds "; 
THINK_BLOCK = "think ", S_VAL;
SWITCH_COSTUME_BLOCK = "switch costume to ", COSTUME
NEXT_COSTUME_BLOCK = "next costume"; 
SWITCH_BACKDROP_BLOCK = "switch backdrop to ", BACKDROP; 
NEXT_BACKDROP_BLOCK = "next backdrop"; 
CHANGE_SIZE_BLOCK = "change size by ", N_VAL; 
SET_SIZE_BLOCK = "set size to ", N_VAL;
CHANGE_VAR_BY_BLOCK = "change ", EFFECT, " effect by ", N_VAL; 
SET_VAR_TO_BLOCK = "set ", EFFECT, " effect to ", N_VAL; 
CLEAR_GRAPHICS_BLOCK = "clear graphic effects"; 
SHOW_BLOCK = "show"; 
HIDE_BLOCK = "hide"; 
GO_TO_LAYER_BLOCK = "go to ", LAYER " layer"; 
GO_TO_NTH_BLOCK = "go ", LAYER_DIRECTION, N_VAL, " layers";

PLAY_UNTIL_BLOCK = "play sound ", VAR, " until done"; 
START_SOUND_BLOCK = "start sound ", VAR; 
STOP_SOUNDS_BLOCK = "stop all sounds"; 
CHANGE_VAR_BY_BLOCK = "change ", SOUND_EFFECT, " effect by ", N_VAL; 
SET_VAR_BY_BLOCK = "set ", SOUND_EFFECT, " effect to ", N_VAL; 
CLEAR_SOUNDS_BLOCK = "clear sounds effects"; 
CHANGE_VOLUME_BLOCK = "change volume by ", N_VAL; 
SET_VOLUME_BLOCK = "set volume to ", N_VAL; 

GREEN_FLAG_BLOCK = "when green flag clicked";
KEY_PRESSED_BLOCK = "when ", KEY, " key pressed"; 
SPRITE_CLICKED_BLOCK = "when this sprite clicked"; 
BACKDROP_SWITCHED_BLOCK = "when backdrop switches to ", backdrop;
WHEN_GREATER_BLOCK = "when", loudness, " > ", N_VAL; 
WHEN_RECEIVE_BLOCK = "when I receive", message; 
BROADCAST_MESSAGE_BLOCK = "broadcast", message;
BROADCAST_THEN_WAIT_BLOCK = "broadcast", message, " and wait"; 

WAIT_BLOCK = "wait", N_VAL, "seconds"; 
REPEAT_BLOCK = "repeat", N_VAL, ;
FOREVER_BLOCK = "forver\t", {BLOCK_TYPE};
IF_BLOCK = "if <", OPERATORS_BLOCK, " then";
IF_ELSE_BLOCK = "if <", OPERATORS_BLOCK, " then\n\t", {BLOCK_TYPE}, "else\n\t";
WAIT_UNTIL_BLOCK = "wait until ", OPERATORS_BLOCK; 
REPEAT_UNTIL_BLOCK = "repeat until ", OPERATORS_BLOCK;
STOP_VAR_BLOCK = "stop ", scripts;
WHEN_START_CLONE_BLOCK = "when I start as a clone"; 
CREATE_CLONE_BLOCK = "create clone of ", "myself"; 
DELETE_CLONE_BLOCK = "delete this clone"; 

TOUCHING_VAR_OPERATOR = "touching ", "mouse-pointer" | "edge", "?";
TOUCHING_COLOR_OPERATOR = "touching color ", color;
COLORS_TOUCHING_OPERATOR = "color ", color, " is touching ", color; 
ASK_WAIT_BLOCK = "ask ", string, " and wait"; 
KEY_PRESSED_OPERATOR = "key ", KEY, "pressed?"; 
MOUSE_CLICKED_OPERATOR = "mouse down?";
SET_DRAG_VAR_BLOCK = "set drag mode ", "draggable " | "not draggable"; 
RESET_TIMER_BLOCK = "reset timer"; 

PLUS_OPERATOR = N_VAL, " + ", N_VAL; 
MINUS_OPEATOR = N_VAL, " - ", N_VAL; 
MULTIPLY_OPERATOR N_VAL, " * ", N_VAL; 
DIVIDE_OPERATOR = N_VAL, " / ", N_VAL; 
RANDOM_OPERATOR = "pick random", N_VAL, "to ", N_VAL; 
GREATER_THAN_BLOCK = N_VAL, " > ", N_VAL; 
LESS_THAN_OPERATOR = N_VAL, " < ", N_VAL; 
EQUALS_OPERATOR = N_VAL, " = ", N_VAL; 
AND_OPERATOR = N_VAL, " and ", N_VAL; 
OR_OPERATOR = N_VAL, " or ", N_VAL; 
NOT_OPERATOR = "not ", N_VAL; 
CONTAINS_OPERATOR = N_VAL, " > ", N_VAL; 
JOIN_OPERATOR = "join ", S_VAL, S_VAL; 
LETTER_OPERATOR = "letter ", N_VAL, " of ", S_VAL; 
LENGTH_OPERATOR = "length of ", S_VAL;
CONTAINS_OPERATOR = N_VAL, " contains ", N_VAL, "?"; 
MOD_OPERATOR = N_VAL | S_VAL, " mod ", N_VAL | S_VAL; 
ROUND_OPERATOR = "round ", N_VAL; 
FUNCTION_OPERATOR = formula, " of ", N_VAL; 

SET_VAR_BLOCK = " set ", VAR, " to ", N_VAL; 
CHANGE_VAR_BLOCK = "change ", VAR, " by ", N_VAL; 
SHOW_VAR_BLOCK = "show variable ", VAR; 
HIDE_VAR_BLOCK = "hide variable ", VAR; 

(Basic Values)
BASIC_TYPES = 
Empty
| Number
| Bool 
| String
(Fundamental Definitions)
Empty = "";
digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;
Bool = "true" | "false";
operators = " " | "(" | ")" | ",";
symbol = ?list of symbols?;
letter = "A" | "B" | "C" | "D" | "E" | "F" | "G"
       | "H" | "I" | "J" | "K" | "L" | "M" | "N"
       | "O" | "P" | "Q" | "R" | "S" | "T" | "U"
       | "V" | "W" | "X" | "Y" | "Z" | "a" | "b"
       | "c" | "d" | "e" | "f" | "g" | "h" | "i"
       | "j" | "k" | "l" | "m" | "n" | "o" | "p"
       | "q" | "r" | "s" | "t" | "u" | "v" | "w"
       | "x" | "y" | "z" ;
number = [ "-" ], digit, { digit } ;
character = letter | digit | symbol | "_" ;
string = character, [{character}];
VAR = "[", string, "]";
N_VAL = number | VAR; 
S_VAL = string | VAR; 
ROT_STYLE = "left-right" | "don't rotate" | "all around"; 
EFFECT = "color" | "fisheye" | "whirl" | "pixelate" | "mosaic" | "brightness" | "ghost"; 
LAYER = "front" | "back"; 
LAYER_DIRECTION = "forward" | "backward"; 
SOUND_EFFECT = "pitch" | "pan left/right"; 
KEY = digit | letter | "space" | "left arrow" | "right arrow" | "down arrow" | "up arrow" | "any";
loudness_timer = loudness | timer;
message = string; 
scripts = "all" | "this script" | "other scripts in sprice"; 
color = "#",[letter|digit]{6};
formula = "abs" | "floor" | "ceiling" | "sqrt" | "sin" | "cos" | "tan" | "asin" | "acos" | "atan" | "ln" | "log" | "e^" | "10^" | ;

When green flag clicked 
show variable [myvar] 
if <myvar <50>> then 
    move 100 steps 
    if edge bounce 
    set [myvar] to (myvar+1) 
else 
    stop all