Update Pratt Parser

1 files changed, 52 insertions, 31 deletions

diff --git a/BJC-Utils2/src/main/java/bjc/utils/parserutils/pratt/PrattParser.java b/BJC-Utils2/src/main/java/bjc/utils/parserutils/pratt/PrattParser.java
index a8c273d..e8543dc 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/parserutils/pratt/PrattParser.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/parserutils/pratt/PrattParser.java
@@ -3,6 +3,8 @@ package bjc.utils.parserutils.pratt;
 import bjc.utils.data.ITree;
 import bjc.utils.funcutils.NumberUtils;
 import bjc.utils.parserutils.ParserException;
+import bjc.utils.parserutils.pratt.commands.DefaultNonInitialCommand;
+import bjc.utils.parserutils.pratt.commands.DefaultInitialCommand;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -13,29 +15,29 @@ import java.util.Map;
  * @author EVE
  * 
  * @param <K>
- *            The key type for the tokens.
+ *                The key type for the tokens.
  * 
  * @param <V>
- *            The value type for the tokens.
+ *                The value type for the tokens.
  * 
  * @param <C>
- *            The state type of the parser.
+ *                The state type of the parser.
  * 
  *
  */
 public class PrattParser<K, V, C> {
-	private final LeftCommand<K, V, C> DEFAULT_LEFT_COMMAND = new DefaultLeftCommand<>();
-	private final NullCommand<K, V, C> DEFAULT_NULL_COMMAND = new DefaultNullCommand<>();
+	private final NonInitialCommand<K, V, C>	DEFAULT_LEFT_COMMAND	= new DefaultNonInitialCommand<>();
+	private final InitialCommand<K, V, C>	DEFAULT_NULL_COMMAND	= new DefaultInitialCommand<>();
 
-	private Map<K, LeftCommand<K, V, C>> leftCommands;
-	private Map<K, NullCommand<K, V, C>> nullCommands;
-	private Map<K, NullCommand<K, V, C>> statementCommands;
+	private Map<K, NonInitialCommand<K, V, C>>	leftCommands;
+	private Map<K, InitialCommand<K, V, C>>	nullCommands;
+	private Map<K, InitialCommand<K, V, C>>	statementCommands;
 
 	/**
 	 * Create a new Pratt parser.
 	 * 
 	 * @param terminal
-	 *            The terminal symbol.
+	 *                The terminal symbol.
 	 */
 	public PrattParser() {
 		leftCommands = new HashMap<>();
@@ -47,22 +49,25 @@ public class PrattParser<K, V, C> {
 	 * Parse an expression.
 	 * 
 	 * @param precedence
-	 *            The initial precedence for the expression.
+	 *                The initial precedence for the expression.
 	 * 
 	 * @param tokens
-	 *            The tokens for the expression.
+	 *                The tokens for the expression.
 	 * 
 	 * @param state
-	 *            The state of the parser.
+	 *                The state of the parser.
+	 * 
+	 * @param isStatement
+	 *                Whether or not to parse statements.
 	 * 
 	 * @return The expression as an AST.
 	 * 
 	 * @throws ParserException
-	 *             If something goes wrong during parsing.
+	 *                 If something goes wrong during parsing.
 	 */
-	public ITree<Token<K, V>> parseExpression(int precedence, TokenStream<K, V> tokens, C state, boolean isStatement)
-			throws ParserException {
-		if (precedence < 0) {
+	public ITree<Token<K, V>> parseExpression(int precedence, TokenStream<K, V> tokens, C state,
+			boolean isStatement) throws ParserException {
+		if(precedence < 0) {
 			throw new IllegalArgumentException("Precedence must be greater than zero");
 		}
 
@@ -71,28 +76,28 @@ public class PrattParser<K, V, C> {
 
 		ITree<Token<K, V>> ast;
 
-		if (isStatement && statementCommands.containsKey(initToken.getKey())) {
-			ast = statementCommands.getOrDefault(initToken.getKey(), DEFAULT_NULL_COMMAND).nullDenotation(initToken,
-					new ParserContext<>(tokens, this, state));
+		if(isStatement && statementCommands.containsKey(initToken.getKey())) {
+			ast = statementCommands.getOrDefault(initToken.getKey(), DEFAULT_NULL_COMMAND)
+					.denote(initToken, new ParserContext<>(tokens, this, state));
 		} else {
-			ast = nullCommands.getOrDefault(initToken.getKey(), DEFAULT_NULL_COMMAND).nullDenotation(initToken,
-					new ParserContext<>(tokens, this, state));
+			ast = nullCommands.getOrDefault(initToken.getKey(), DEFAULT_NULL_COMMAND)
+					.denote(initToken, new ParserContext<>(tokens, this, state));
 		}
 
 		int rightPrec = Integer.MAX_VALUE;
 
-		while (true) {
+		while(true) {
 			Token<K, V> tok = tokens.current();
 
 			K key = tok.getKey();
 
-			LeftCommand<K, V, C> command = leftCommands.getOrDefault(key, DEFAULT_LEFT_COMMAND);
+			NonInitialCommand<K, V, C> command = leftCommands.getOrDefault(key, DEFAULT_LEFT_COMMAND);
 			int leftBind = command.leftBinding();
 
-			if (NumberUtils.between(precedence, rightPrec, leftBind)) {
+			if(NumberUtils.between(precedence, rightPrec, leftBind)) {
 				tokens.next();
 
-				ast = command.leftDenote(ast, tok, new ParserContext<>(tokens, this, state));
+				ast = command.denote(ast, tok, new ParserContext<>(tokens, this, state));
 				rightPrec = command.nextBinding();
 			} else {
 				break;
@@ -106,12 +111,12 @@ public class PrattParser<K, V, C> {
 	 * Add a non-initial command to this parser.
 	 * 
 	 * @param marker
-	 *            The key that marks the command.
+	 *                The key that marks the command.
 	 * 
 	 * @param comm
-	 *            The command.
+	 *                The command.
 	 */
-	public void addNonInitialCommand(K marker, LeftCommand<K, V, C> comm) {
+	public void addNonInitialCommand(K marker, NonInitialCommand<K, V, C> comm) {
 		leftCommands.put(marker, comm);
 	}
 
@@ -119,12 +124,28 @@ public class PrattParser<K, V, C> {
 	 * Add a initial command to this parser.
 	 * 
 	 * @param marker
-	 *            The key that marks the command.
+	 *                The key that marks the command.
 	 * 
 	 * @param comm
-	 *            The command.
+	 *                The command.
 	 */
-	public void addInitialCommand(K marker, NullCommand<K, V, C> comm) {
+	public void addInitialCommand(K marker, InitialCommand<K, V, C> comm) {
 		nullCommands.put(marker, comm);
 	}
+
+	/**
+	 * Add a statement command to this parser.
+	 * 
+	 * The difference between statements and initial commands is that
+	 * statements can only appear at the start of the expression.
+	 * 
+	 * @param marker
+	 *                The key that marks the command.
+	 * 
+	 * @param comm
+	 *                The command.
+	 */
+	public void addStatementCommand(K marker, InitialCommand<K, V, C> comm) {
+		statementCommands.put(marker, comm);
+	}
 }