Add TreesUser class for improved tree representation and update grammar rules

Q1/Artefacts/RobotLang.g4

@@ -18,6 +18,6 @@ logStat: 'LOG' STRING ';' ;
 repeatStat: 'REPEAT' NUMBER '{' stat+ '}' ;
 
 ID_PREFIX: '// STUDENT ID:' ;
-NUMBER: [0-9]+ ;
+NUMBER: [1-9]+ ;
-STRING: '"' .*? '"' {self.text = self.text[1:-1]} ;
+STRING: '"' .*? '"' ;
 WS: [ \t\r\n]+ -> skip ;

Q1/Artefacts/TreesUser.py

@@ -0,0 +1,27 @@
+from antlr4.Utils import escapeWhitespace
+from antlr4.tree.Tree import Tree
+from antlr4.tree.Trees import Trees
+
+# need forward declaration
+Parser  = None
+
+class TreesUser(Trees):
+
+    # Print out a whole tree in prettier form
+    # Based on Trees.toStringTree()
+    # indent is the number of indents to use in the display
+    @classmethod
+    def PrettyPrint(cls, t:Tree, ruleNames:list=None, recog:Parser=None, indent:int=0):
+        # indentation is the indent to actually display
+        indentation = ''
+        for n in range(indent):
+            indentation += '   '
+        if recog is not None:
+            ruleNames = recog.ruleNames
+        s = escapeWhitespace(cls.getNodeText(t, ruleNames), False)
+        retval = indentation + s + "\n"
+        if t.getChildCount()>0:
+            # we have children to deal with
+            for i in range(0, t.getChildCount()):
+                retval += cls.PrettyPrint(t.getChild(i), ruleNames, indent=indent+1)
+        return retval

Q1/Artefacts/main.py

@@ -5,21 +5,19 @@ from RobotLangParser import RobotLangParser
 from RobotLangVisitorUser import RobotLangVisitorUser
 
 def main(argv):
-    # Determine if reading from a file or standard input
     if len(argv) == 1:
         inpstream = StdinStream()
     else:
         inpname = argv[1]
         inpstream = FileStream(inpname)
-    # Lexer analyses the characters
     lexer = RobotLangLexer(inpstream)
-    # Create a stream of tokens
+    #Create a stream of tokens
     tokstream = CommonTokenStream(lexer)
-    # Parser produces the abstract syntax tree
+    #Parser produces the abstract syntax tree
     parser = RobotLangParser(tokstream)
-    # Start parsing from the top rule
+    #Start parsing from the top rule
     tree = parser.prog()
-
+    #execute script
     visitor = RobotLangVisitorUser()
     visitor.visit(tree)