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diff --git a/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/constants/singletons/NullCheck.java b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/constants/singletons/NullCheck.java
new file mode 100644
index 000000000..3089a1862
--- /dev/null
+++ b/bundles/org.simantics.scl.compiler/src/org/simantics/scl/compiler/constants/singletons/NullCheck.java
@@ -0,0 +1,49 @@
+package org.simantics.scl.compiler.constants.singletons;
+
+import org.objectweb.asm.Label;
+import org.simantics.scl.compiler.constants.ComparisonFunction;
+import org.simantics.scl.compiler.constants.FunctionValue;
+import org.simantics.scl.compiler.internal.codegen.continuations.Cont;
+import org.simantics.scl.compiler.internal.codegen.references.Val;
+import org.simantics.scl.compiler.internal.codegen.utils.MethodBuilder;
+import org.simantics.scl.compiler.types.TVar;
+import org.simantics.scl.compiler.types.Type;
+import org.simantics.scl.compiler.types.Types;
+import org.simantics.scl.compiler.types.kinds.Kinds;
+
+public class NullCheck extends FunctionValue implements ComparisonFunction {
+    private static final TVar A = Types.var(Kinds.STAR);
+    public static final NullCheck INSTANCE = 
+            new NullCheck();
+    
+    private NullCheck() {
+        super(new TVar[] {A}, Types.NO_EFFECTS, Types.BOOLEAN, A);
+    }
+        
+    @Override
+    public Type applyExact(MethodBuilder mb, Val[] parameters) {
+        parameters[0].push(mb);
+        Label join = mb.createLabel();
+        Label isNull = mb.createLabel();
+        mb.ifNullBranch(isNull, true);
+        mb.loadConstant(false);
+        mb.branch(join);
+        mb.setLocation(isNull);
+        mb.loadConstant(true);
+        mb.setLocation(join);
+        return getReturnType();
+    }
+    
+    @Override
+    public void generateCondition(MethodBuilder mb, Val[] parameters, Cont then_, Cont else_) {
+        parameters[0].push(mb);
+        mb.ifNullBranch(mb.getLabel(then_), true);
+        mb.jump(else_);
+        mb.ensureExists(then_);
+    }
+
+    @Override
+    public String toString() {
+         return "nullCheck";
+    }
+}