TODO tagging

1 files changed, 47 insertions, 61 deletions

diff --git a/dice-lang/src/bjc/dicelang/expr/Parser.java b/dice-lang/src/bjc/dicelang/expr/Parser.java
index 6d34b96..5fa2d3d 100644
--- a/dice-lang/src/bjc/dicelang/expr/Parser.java
+++ b/dice-lang/src/bjc/dicelang/expr/Parser.java
@@ -13,6 +13,10 @@ import bjc.utils.parserutils.TreeConstructor;
  * @author Ben Culkin
  */
 public class Parser {
+	/*
+	 * @TODO 10/08/17 Ben Culkin :MainSeperation
+	 * 	This main method should be moved to its own class.
+	 */
 	/**
 	 * Main method.
 	 *
@@ -20,100 +24,81 @@ public class Parser {
 	 *                Unused CLI args.
 	 */
 	public static void main(final String[] args) {
-		/*
-		 * Create our objects.
-		 */
+		/* Create our objects. */
 		final Tokens toks = new Tokens();
 		final Lexer lex = new Lexer();
 
-		/*
-		 * Prepare our input.
-		 */
+		/* Prepare our input source. */
 		final Scanner scan = new Scanner(System.in);
 
-		/*
-		 * Read initial command.
-		 */
+		/* Read initial command. */
 		System.out.print("Enter a math expression (blank line to quit): ");
 		String ln = scan.nextLine().trim();
 
-		/*
-		 * Enter REPL loop.
-		 */
+		/* Enter REPL loop. */
 		while (!ln.equals("")) {
-			/*
-			 * Print raw command.
-			 */
+			/* Print raw command. */
 			System.out.println("Raw command: " + ln);
 			System.out.println();
 
-			/*
-			 * Lex command to infix tokens.
-			 */
+			/* Lex command to infix tokens. */
 			final Token[] infixTokens = lex.lexString(ln, toks);
 			System.out.println("Lexed tokens: ");
-
 			for (final Token tok : infixTokens) {
 				System.out.println("\t" + tok);
 			}
 
-			/*
-			 * Print out infix expression.
-			 */
+			/* Print out infix expression. */
 			System.out.print("Lexed expression: ");
-
 			for (final Token tok : infixTokens) {
 				System.out.print(tok.toExpr() + " ");
 			}
 
+			/* Space stages. */
 			System.out.println();
 			System.out.println();
 
-			/*
-			 * Shunt infix tokens to postfix tokens.
-			 */
+			/* Shunt infix tokens to postfix tokens. */
 			final Token[] postfixTokens = Shunter.shuntTokens(infixTokens);
 			System.out.println("Lexed tokens: ");
-
 			for (final Token tok : postfixTokens) {
 				System.out.println("\t" + tok);
 			}
 
-			/*
-			 * Print out postfix tokens.
-			 */
+			/* Print out postfix tokens. */
 			System.out.print("Shunted expression: ");
-
 			for (final Token tok : postfixTokens) {
 				System.out.print(tok.toExpr() + " ");
 			}
 
+			/* Space stages. */
 			System.out.println();
 			System.out.println();
 
-			final FunctionalList<Token> tokList = new FunctionalList<>(Arrays.asList(postfixTokens));
+			/* Construct a list from the array of tokens. */
+			final FunctionalList<Token> tokList = new FunctionalList<>(
+					Arrays.asList(postfixTokens));
+
+			/* Construct a tree from the list of postfixed tokens. */
 			final ITree<Token> ast = TreeConstructor.constructTree(tokList,
-			                         tok -> tok.typ.isOperator);
+					tok -> tok.typ.isOperator);
 
-			/*
-			 * Print the tree, then the canonical expression for it.
-			 */
+			/* Print the tree, then the canonical expression for it. */
 			System.out.println("Parsed tree");
 			System.out.println(ast.toString());
 			System.out.println("\nCanonical expr: " + toCanonicalExpr(ast));
 
+			/* Space stages. */
+			System.out.println();
 			System.out.println();
 
-			/*
-			 * Prompt for a new expression.
-			 */
+			/* Prompt for a new expression. */
 			System.out.print("Enter a math expression (blank line to quit): ");
+			/* Read it. */
 			ln = scan.nextLine().trim();
 		}
 
-		/*
-		 * Cleanup after ourselves.
-		 */
+		/* Cleanup after ourselves. */
 		scan.close();
 	}
 
@@ -124,38 +109,39 @@ public class Parser {
 	private static String toCanonicalExpr(final ITree<Token> ast) {
 		final Token data = ast.getHead();
 
-		if (ast.getChildrenCount() == 0)
-			/*
-			 * Handle leaf nodes.
-			 */
-		{
+		if (ast.getChildrenCount() == 0) {
+			/* Handle leaf nodes. */
 			return data.toExpr();
 		}
 
-		final ITree<Token> left = ast.getChild(0);
+		/* The left/right children. */
+		final ITree<Token> left  = ast.getChild(0);
 		final ITree<Token> right = ast.getChild(1);
 
-		String leftExpr = toCanonicalExpr(left);
+		/* Recursively canonicalize them. */
+		String leftExpr  = toCanonicalExpr(left);
 		String rightExpr = toCanonicalExpr(right);
 
-		/*
-		 * Add parens if the left was higher priority.
-		 */
+		/* Add parens if the left was higher priority. */
 		if (left.getChildrenCount() == 0) {
-			if (left.getHead().typ.operatorPriority >= data.typ.operatorPriority) {
-				leftExpr = "(" + leftExpr + ")";
+			int leftPriority = left.getHead().typ.operatorPriority;
+			int dataPriority = data.typ.operatorPriority;
+
+			if (leftPriority >= dataPriority) {
+				leftExpr = String.format("(%s)", leftExpr);
 			}
 		}
 
-		/*
-		 * Add parens if the right was higher priority.
-		 */
+		/* Add parens if the right was higher priority. */
 		if (right.getChildrenCount() == 0) {
-			if (right.getHead().typ.operatorPriority >= data.typ.operatorPriority) {
-				rightExpr = "(" + rightExpr + ")";
+			int rightPriority = right.getHead().typ.operatorPriority;
+			int dataPriority  = data.typ.operatorPriority;
+
+			if (rightPriority >= dataPriority) {
+				rightExpr = String.format("(%s)", rightExpr);
 			}
 		}
 
-		return leftExpr + " " + data.toExpr() + " " + rightExpr;
+		return String.format("%s %s %s", leftExpr, data.toExpr(), rightExpr);
 	}
-}
\ No newline at end of file
+}