patterns

1 files changed, 17 insertions, 0 deletions

diff --git a/sources/scala/runtime/matching/PatternGrammar.scala b/sources/scala/runtime/matching/PatternGrammar.scala
new file mode 100644
index 0000000000..6fcb210b7e
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+++ b/sources/scala/runtime/matching/PatternGrammar.scala
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+package scala.runtime.matching ;
+
+import scala.util.alphabet.IntAlphabet ;
+import scala.collection.{ immutable, mutable, Map, Set };
+
+/** runtime representation of patterns. This class augments
+ *  scala.util.grammar.TreeHedgeGrammar, with an abstract representation
+ *  of variable bindings. Variables are simply consecutive integers,
+ *  following pre-order of occurrence in pattern
+ *  @caseVars an array, field i holding the number of variables in case i
+ */
+abstract class PatternGrammar extends scala.util.grammar.ImmutableTreeHedgeGrammar[IntAlphabet] {
+
+  val vars:Array[Int];
+
+  def test(test:Int, inp:Any): Boolean;
+}