Prefix index variables by %

1 files changed, 10 insertions, 7 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/tensor/functions/Generate.java b/vespajlib/src/main/java/com/yahoo/tensor/functions/Generate.java
index aaed607aaa1..d3a2dc9169c 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/functions/Generate.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/functions/Generate.java
@@ -145,17 +145,15 @@ public class Generate<NAMETYPE extends TypeContext.Name>  extends PrimitiveTenso
 
         @Override
         public Tensor getTensor(String name) {
-            Optional<Integer> index = type.indexOfDimension(name);
-            if (index.isPresent()) // this is the name of a dimension
-                return Tensor.from(indexes.indexesForReading()[index.get()]);
+            if (name.startsWith("%")) // this is the name of a dimension
+                return Tensor.from(indexes.indexesForReading()[dimensionIndexFrom(name)]);
             else
                 return context.getTensor(name);
         }
 
         @Override
         public TensorType getType(NAMETYPE name) {
-            Optional<Integer> index = type.indexOfDimension(name.name());
-            if (index.isPresent()) // this is the name of a dimension
+            if (name.name().startsWith("%")) // this is the name of a dimension
                 return TensorType.empty;
             else
                 return context.getType(name);
@@ -163,13 +161,18 @@ public class Generate<NAMETYPE extends TypeContext.Name>  extends PrimitiveTenso
 
         @Override
         public TensorType getType(String name) {
-            Optional<Integer> index = type.indexOfDimension(name);
-            if (index.isPresent()) // this is the name of a dimension
+            if (name.startsWith("%")) // this is the name of a dimension
                 return TensorType.empty;
             else
                 return context.getType(name);
         }
 
+        private int dimensionIndexFrom(String nameWithPercentage) {
+            String name = nameWithPercentage.substring(1);
+            return type.indexOfDimension(name)
+                       .orElseThrow(() -> new IllegalArgumentException("No dimension '" + name + "' in " + type));
+        }
+
     }
 
 }