Description
Email, or “PING” me a zip file with your code and any supporting files.
What Needs to be submitted and Completeness:
All submitted assignments must actually work for even partial credit.
• Your .g4 grammar file
• Your python code.. Feel free to Zip up your entire working directory.
• Screen Shot of the Turtle Drawing
Assignment Motivation:
• Write a simple language that can be compiled directly a turtle/tool path.
• Write a formal grammar
• Compile a formal grammar into language specific libraries
• Code a “G” code compiler
• Resume Building
• Formal Grammar
• Compiler Design and Implementation
• Antlr
• Python
• G Codes
current position
• Write a test input file that draws a square
• Screen Shot the Square
• Grade of B
• Grade of C plus implement one additional G-CODE, for Example:
• G28
• F
• Z
• Output should demonstrate the additional implemented code
• Grade of A
• Grade of B plus at least one more G-Code
• Output something more interesting than a square
The Assignment Resources:
• G Code Reference
• https://en.wikipedia.org/wiki/G-code
• If you need Java
• https://www.oracle.com/java/technologies/downloads/#jdk17-mac
• If you need Python
• https://www.anaconda.com/products/individual
• Antlr Getting Started
• https://github.com/antlr/antlr4/blob/master/doc/getting-started.md
• Example Calculator
• https://medium.com/@raguiar2/building-a-working-calculator-in-python-with-antlr-d879e2ea9058
• Python Turtle Library
• https://docs.python.org/3/library/turtle.html
• Get Antlr jar
• curl -O https://www.antlr.org/download/antlr-4.9-complete.jar
• Setup Alias in linux.. Anrtlr “Getting Started” above shows how to do on windows
• alias antlr4=’java -Xmx500M -cp “./antlr-4.9-complete.jar:$CLASSPATH” org.antlr.v4.Tool’
• alias grun=’java -Xmx500M -cp “./antlr-4.9-complete.jar:$CLASSPATH” org.antlr.v4.gui.TestRig’
• Generate Lexer, Parser, Visitor
• antlr4 -Dlanguage=Python3 -visitor turtle.g4
• NEEDED!!! Load Antlr python runtime libs
• pip install antlr4-python3-runtime
turtle.g4
grammar turtle;
start : expr | <EOF> ;
expr : ‘turtle’ x_cord=NUMBER y_cord=NUMBER #drawlineExpr
| ‘print’ x_cord=NUMBER y_cord=NUMBER #printlineExpr
;
NUMBER : (‘0’ .. ‘9’) + (‘.’ (‘0’ .. ‘9’) +)? ;
turtle_test (input file)
turtle 100 200
turtle 300 400
print 3 4
run_me.py
from antlr4 import *
from turtleLexer import turtleLexer
from turtleParser import turtleParser
from turtleVisitor import turtleVisitor
import time
def main():
lexer = turtleLexer (FileStream(“turtle_test”))
token_stream = CommonTokenStream(lexer)
parser = turtleParser(token_stream)
visitor = turtleVisitor()
while True:
tree = parser.start()
if tree.expr() == None:
break
print(tree.toStringTree(recog=parser))
visitor.visit(tree)
time.sleep(2)
if __name__ == ‘__main__’:
main()
turtleVisitor.py
# Generated from turtle.g4 by ANTLR 4.9
from antlr4 import *
from turtleAst import *
if __name__ is not None and “.” in __name__:
from .turtleParser import turtleParser
else:
from turtleParser import turtleParser
# This class defines a complete generic visitor for a parse tree produced by turtleParser.
import turtle
skk = turtle.Turtle()
class turtleVisitor(ParseTreeVisitor):
# Visit a parse tree produced by turtleParser#start.
def visitStart(self, ctx:turtleParser.StartContext):
return self.visitChildren(ctx)
# Visit a parse tree produced by turtleParser#drawlineExpr.
def visitDrawlineExpr(self, ctx:turtleParser.DrawlineExprContext):
target_x = int(ctx.x_cord.text)
target_y = int(ctx.y_cord.text)
cur_pos = skk.pos()
if target_x > cur_pos[0]:
skk.right(target_x – cur_pos[0])
else:
skk.left(cur_pos[0] – target_x)
if target_y > cur_pos[0]:
skk.forward(target_y – cur_pos[0])
else:
skk.backward(cur_pos[0] – target_y)
return self.visitChildren(ctx)
# Visit a parse tree produced by turtleParser#printlineExpr.
def visitPrintlineExpr(self, ctx:turtleParser.PrintlineExprContext):
print(f”Draw Line to {ctx.x_cord.text} {ctx.y_cord.text}”)
return self.visitChildren(ctx)
del turtleParser
