Fix for TPC-H Q2 not reaching a fix point

astral/catalyst/src/com/astraldb/catalyst/Generate.scala

@@ -37,6 +37,7 @@ object Generate
                  |import org.apache.spark.sql.catalyst.plans.logical._
                  |import org.apache.spark.sql.catalyst.expressions._
                  |import com.astraldb.catalyst.SparkMethods._
+                 |import scala.collection.mutable
                  |""".stripMargin)
       of.write(content)
       of.close()

astral/compiler/src/com/astraldb/codegen/Optimizer.scala

@@ -12,6 +12,6 @@ object Optimizer
 
   def bdd(family: Type.AST): String =
   {
-    scala.Optimizer(Seq(s"${family.scalaType}BDD"), s"${family.scalaType}BDDOptimizer").toString
+    scala.BDDOptimizer(Seq(s"${family.scalaType}BDD"), s"${family.scalaType}BDDOptimizer").toString
   }
 }

astral/compiler/views/com/astraldb/codegen/BDDOptimizer.scala.scala

@@ -0,0 +1,40 @@
+@import com.astraldb.spec.Definition
+
+@(rules: Seq[String], clazz: String = "Optimizer")
+
+object @clazz
+{
+  val rules = Seq[Rule[LogicalPlan]](
+    @for(rule <- rules){ @rule , 
+    }
+  )
+
+  def MAX_ITERATIONS = 100
+
+  def rewrite(plan: LogicalPlan): (LogicalPlan, Int) =
+  {
+    var current = plan
+    var last = plan
+
+    val hashPlanSet = mutable.Set[Int]()
+
+    hashPlanSet.add(plan.hashCode)
+    for(i <- 0 until MAX_ITERATIONS)
+    {
+      for(rule <- rules)
+      {
+        current = rule(current)
+        if(!hashPlanSet.add(current.hashCode))
+        {
+          return (current, i+1)
+        }
+      }
+      if(last.fastEquals(current))
+      {
+        return (current, i+1)
+      }
+      last = current
+    }
+    return (current, MAX_ITERATIONS)
+  }
+}

docs/LANG.md

@@ -1 +1,9 @@
-# ASTral Language Specification
+# Compiling and runing ASTral
+1. Set JAVA_HOME correctly: 
+    echo $JAVA_HOME
+    echo $(/usr/libexec/java_home)
+    export JAVA_HOME=$(/usr/libexec/java_home)
+2. mill clean
+3. mill astral.catalyst.impl.compile
+4. To run TPCH tests: mill astral.catalyst.impl.runMain com.astraldb.catalyst.TPCHTest 
+# ASTral Language Specification