collect variables from patterns

1 files changed, 35 insertions, 0 deletions

diff --git a/sources/scalac/transformer/matching/CollectVariableTraverser.java b/sources/scalac/transformer/matching/CollectVariableTraverser.java
new file mode 100644
index 0000000000..5223bdee46
--- /dev/null
+++ b/sources/scalac/transformer/matching/CollectVariableTraverser.java
@@ -0,0 +1,35 @@
+package scalac.transformer.matching ;
+
+import scalac.util.Name ;
+import scalac.ast.Tree ;
+import scalac.symtab.Symbol ;
+
+import java.util.Vector;
+
+class CollectVariableTraverser extends VariableTraverser {
+
+      Vector vars;
+
+      boolean isVariableName( Name name ) {
+            return ( name.toString().indexOf("$") == -1 )
+                  && super.isVariableName( name );
+      }
+
+
+      void handleVariableSymbol( Symbol sym ) {
+            vars.add( sym );
+      }
+
+      public CollectVariableTraverser() {
+            this.vars = new Vector();
+      }
+
+      static  boolean containsBinding( Tree  pat ) {
+
+            CollectVariableTraverser cvt = new CollectVariableTraverser();
+            cvt.traverse( pat );
+            return !cvt.vars.isEmpty();
+
+      }
+
+}