1 files changed, 86 insertions, 0 deletions
diff --git a/JPratt/src/main/java/com/ashardalon/pratt/blocks/ChainParseBlock.java b/JPratt/src/main/java/com/ashardalon/pratt/blocks/ChainParseBlock.java
new file mode 100644
index 0000000..fe04070
--- /dev/null
+++ b/JPratt/src/main/java/com/ashardalon/pratt/blocks/ChainParseBlock.java
@@ -0,0 +1,86 @@
+package com.ashardalon.pratt.blocks;
+
+import java.util.Set;
+
+import com.ashardalon.pratt.ParserContext;
+import com.ashardalon.pratt.commands.CommandResult;
+import com.ashardalon.pratt.commands.CommandResult.Status;
+import com.ashardalon.pratt.tokens.Token;
+
+import bjc.data.Tree;
+import bjc.data.SimpleTree;
+import bjc.utils.parserutils.ParserException;
+
+/**
+ * A {@link ParseBlock} for a series of parse blocks, linked by a set of tokens.
+ * 
+ * Roughly analogous to Perl 6s list associative operators.
+ * 
+ * @author bjculkin
+ * 
+ * @param <K>
+ *        The token key type.
+ * 
+ * @param <V>
+ *        The token value type.
+ * 
+ * @param <C>
+ *        The parser state type.
+ *
+ */
+public class ChainParseBlock<K, V, C> implements ParseBlock<K, V, C> {
+	private ParseBlock<K, V, C> iner;
+
+	private Set<K> indicators;
+
+	private Token<K, V> trm;
+
+	/**
+	 * Create a new chain parser block.
+	 * 
+	 * @param inner
+	 *        The block for the chains interior.
+	 * 
+	 * @param chainIndicators
+	 *        The set of markers that indicate continuing the chain
+	 * 
+	 * @param term
+	 *        The node in the AST for the expression.
+	 */
+	public ChainParseBlock(ParseBlock<K, V, C> inner, Set<K> chainIndicators, Token<K, V> term) {
+		iner = inner;
+		indicators = chainIndicators;
+		trm = term;
+	}
+
+	@Override
+	public CommandResult<K, V> parse(ParserContext<K, V, C> ctx) throws ParserException {
+		CommandResult<K,V> resOuter = iner.parse(ctx);
+		if (resOuter.status != Status.SUCCESS) return resOuter;
+		
+		Tree<Token<K, V>> expression = resOuter.success();
+		Token<K, V> currentToken = ctx.tokens.current();
+		if(indicators.contains(currentToken.getKey())) {
+			Tree<Token<K, V>> res = new SimpleTree<>(trm);
+			res.addChild(expression);
+
+			while(indicators.contains(currentToken.getKey())) {
+				res.addChild(new SimpleTree<>(currentToken));
+				ctx.tokens.next();
+
+				CommandResult<K,V> resInner = iner.parse(ctx);
+				if (resInner.status != Status.SUCCESS) return resInner;
+				
+				Tree<Token<K, V>> innerExpression = resInner.success();
+				res.addChild(innerExpression);
+
+				currentToken = ctx.tokens.current();
+			}
+
+			return CommandResult.success(res);
+		}
+
+		return resOuter;
+	}
+
+}