Fix optimization in use statement and match expression with _ matcher

ownlang-desktop/build.gradle

@@ -47,3 +47,13 @@ tasks.register('runOptimizing', JavaExec) {
     ignoreExitValue true
     args '-o 9 -m -a -f ../program.own'.split(' ')
 }
+
+tasks.register('runOptimizationDumper', JavaExec) {
+    group = "application"
+    description = "Run optmizer and dump results"
+    dependsOn classes
+    mainClass = 'com.annimon.ownlang.utils.OptimizationDumper'
+    classpath = sourceSets.main.runtimeClasspath
+    args '../program.own'
+}
+//

ownlang-parser/src/main/java/com/annimon/ownlang/parser/ast/MatchExpression.java

@@ -74,7 +74,7 @@ public final class MatchExpression extends InterruptableNode implements Expressi
         final int size = array.size();
         for (int i = 0; i < size; i++) {
             final Expression expr = p.values.get(i);
-            if ( (expr != TuplePattern.ANY) && (expr.eval().compareTo(array.get(i)) != 0) ) {
+            if ( (expr != ANY) && (expr.eval().compareTo(array.get(i)) != 0) ) {
                 return false;
             }
         }
@@ -279,8 +279,9 @@ public final class MatchExpression extends InterruptableNode implements Expressi
             }
             return "()".concat(super.toString());
         }
+    }
 
-        private static final Expression ANY = new Expression() {
+    public static final Expression ANY = new Expression() {
         @Override
         public Value eval() {
             return NumberValue.ONE;
@@ -297,8 +298,7 @@ public final class MatchExpression extends InterruptableNode implements Expressi
 
         @Override
         public String toString() {
-                return "_".concat(super.toString());
+            return "_";
         }
     };
-    }
 }

ownlang-parser/src/main/java/com/annimon/ownlang/parser/optimization/ConstantFolding.java

@@ -99,11 +99,6 @@ public class ConstantFolding extends OptimizationVisitor<Void> implements Optimi
         return super.visit(s, t);
     }
 
-    @Override
-    public Node visit(UseStatement s, Void unused) {
-        return null;
-    }
-
     @Override
     public Node visit(FunctionDefineStatement s, Void t) {
         if (OPERATORS.contains(s.name)) {

ownlang-parser/src/main/java/com/annimon/ownlang/parser/optimization/OptimizationVisitor.java

@@ -280,11 +280,13 @@ public abstract class OptimizationVisitor<T> implements ResultVisitor<Node, T> {
                 final List<Expression> newValues = new ArrayList<>(tuple.values.size());
                 boolean valuesChanged = false;
                 for (Expression value : tuple.values) {
+                    if (value != MatchExpression.ANY) {
                         final Node node = value.accept(this, t);
                         if (node != value) {
                             valuesChanged = true;
                             value = (Expression) node;
                         }
+                    }
                     newValues.add(value);
                 }
                 if (valuesChanged) {