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authorbculkin2442 <bjculkin@mix.wvu.edu>2016-03-28 08:47:23 -0400
committerbculkin2442 <bjculkin@mix.wvu.edu>2016-03-28 08:47:23 -0400
commit62e94ef994a59e87543445bb3c0ce0a37017a70a (patch)
treedfa1a488d3929e3f93e2a91669cdaf97c6d707f3 /dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java
parent78d9c539e25f16fd15f06c2b2c48c0ad37a21540 (diff)
Renamed packages to suit updated project
Diffstat (limited to 'dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java')
-rw-r--r--dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java114
1 files changed, 114 insertions, 0 deletions
diff --git a/dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java b/dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java
new file mode 100644
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+++ b/dice-lang/src/main/java/bjc/dicelang/ast/DiceASTFlattener.java
@@ -0,0 +1,114 @@
+package bjc.dicelang.ast;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.BinaryOperator;
+
+import org.apache.commons.lang3.StringUtils;
+
+import bjc.dicelang.BindingDiceExpression;
+import bjc.dicelang.ComplexDice;
+import bjc.dicelang.CompoundDice;
+import bjc.dicelang.CompoundDiceExpression;
+import bjc.dicelang.DiceExpressionType;
+import bjc.dicelang.IDiceExpression;
+import bjc.dicelang.ReferenceDiceExpression;
+import bjc.dicelang.ScalarDie;
+import bjc.utils.parserutils.AST;
+
+/**
+ * Flatten an {@link AST} of {@link IDiceASTNode} into a
+ * {@link IDiceExpression}
+ *
+ * @author ben
+ *
+ */
+public class DiceASTFlattener {
+ /**
+ * Build the operations to use for tree flattening
+ *
+ * @param env
+ * The enviroment the tree will be flattened against
+ * @return The operations needed for tree flattening
+ */
+ private static Map<IDiceASTNode, BinaryOperator<IDiceExpression>>
+ buildOperations(Map<String, IDiceExpression> env) {
+ Map<IDiceASTNode, BinaryOperator<IDiceExpression>> opCollapsers =
+ new HashMap<>();
+ opCollapsers.put(OperatorDiceNode.ADD, (left, right) -> {
+ return new CompoundDiceExpression(right, left,
+ DiceExpressionType.ADD);
+ });
+ opCollapsers.put(OperatorDiceNode.SUBTRACT, (left, right) -> {
+ return new CompoundDiceExpression(right, left,
+ DiceExpressionType.SUBTRACT);
+ });
+ opCollapsers.put(OperatorDiceNode.MULTIPLY, (left, right) -> {
+ return new CompoundDiceExpression(right, left,
+ DiceExpressionType.MULTIPLY);
+ });
+ opCollapsers.put(OperatorDiceNode.DIVIDE, (left, right) -> {
+ return new CompoundDiceExpression(right, left,
+ DiceExpressionType.DIVIDE);
+ });
+ opCollapsers.put(OperatorDiceNode.ASSIGN, (left, right) -> {
+ return new BindingDiceExpression(left, right, env);
+ });
+ opCollapsers.put(OperatorDiceNode.COMPOUND, (left, right) -> {
+ return new CompoundDice(left, right);
+ });
+ opCollapsers.put(OperatorDiceNode.GROUP, (left, right) -> {
+ return new ComplexDice(left, right);
+ });
+
+ return opCollapsers;
+ }
+
+ /**
+ * Create a dice expression from a literal token
+ *
+ * @param tok
+ * The token to convert to an expression
+ * @return The dice expression represented by the token
+ */
+ private static IDiceExpression expFromLiteral(LiteralDiceNode tok) {
+ String data = tok.getData();
+
+ if (StringUtils.countMatches(data, 'c') == 1
+ && !data.equalsIgnoreCase("c")) {
+ String[] strangs = data.split("c");
+
+ return new CompoundDice(ComplexDice.fromString(strangs[0]),
+ ComplexDice.fromString(strangs[1]));
+ } else if (StringUtils.countMatches(data, 'd') == 1
+ && !data.equalsIgnoreCase("d")) {
+ return ComplexDice.fromString(data);
+ } else {
+ return new ScalarDie(Integer.parseInt(data));
+ }
+ }
+
+ /**
+ * Flatten a AST into a dice expression
+ *
+ * @param ast
+ * The AST to flatten
+ * @param env
+ * The enviroment to flatten against
+ * @return The AST, flattened into a dice expression
+ */
+ public static IDiceExpression flatten(AST<IDiceASTNode> ast,
+ Map<String, IDiceExpression> env) {
+ Map<IDiceASTNode, BinaryOperator<IDiceExpression>> opCollapsers =
+ buildOperations(env);
+
+ return ast.collapse((nod) -> {
+ if (nod instanceof LiteralDiceNode) {
+ return expFromLiteral((LiteralDiceNode) nod);
+ } else {
+ return new ReferenceDiceExpression(
+ ((VariableDiceNode) nod).getVariable(), env);
+ }
+ } , opCollapsers::get, (r) -> r);
+ }
+}