diff --git a/src/main/java/dk/camelot64/kickc/model/operators/Operator.java b/src/main/java/dk/camelot64/kickc/model/operators/Operator.java
index 37ac6a60c..57b011772 100644
--- a/src/main/java/dk/camelot64/kickc/model/operators/Operator.java
+++ b/src/main/java/dk/camelot64/kickc/model/operators/Operator.java
@@ -1,5 +1,11 @@
 package dk.camelot64.kickc.model.operators;
 
+import dk.camelot64.kickc.model.CompileError;
+import dk.camelot64.kickc.model.values.ConstantBool;
+import dk.camelot64.kickc.model.values.ConstantEnumerable;
+import dk.camelot64.kickc.model.values.ConstantInteger;
+import dk.camelot64.kickc.model.values.ConstantLiteral;
+
 import java.io.Serializable;
 
 /**
@@ -64,4 +70,12 @@ public class Operator implements Serializable {
       return result;
    }
 
+   static Boolean getBool(ConstantLiteral literal) {
+      if(literal instanceof ConstantBool)
+         return ((ConstantBool) literal).getBool();
+      if(literal instanceof ConstantEnumerable)
+         return !((ConstantEnumerable) literal).getInteger().equals(0L);
+      throw new CompileError("Not a boolean" + literal);
+   }
+
 }
diff --git a/src/main/java/dk/camelot64/kickc/model/operators/OperatorBinary.java b/src/main/java/dk/camelot64/kickc/model/operators/OperatorBinary.java
index 2055a15eb..da66e1ba9 100644
--- a/src/main/java/dk/camelot64/kickc/model/operators/OperatorBinary.java
+++ b/src/main/java/dk/camelot64/kickc/model/operators/OperatorBinary.java
@@ -33,4 +33,7 @@ public abstract class OperatorBinary extends Operator {
    public boolean isAssociative() {
       return associative;
    }
+
+
+
 }
diff --git a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicAnd.java b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicAnd.java
index a22d2253d..cd5ac834d 100644
--- a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicAnd.java
+++ b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicAnd.java
@@ -3,6 +3,7 @@ package dk.camelot64.kickc.model.operators;
 import dk.camelot64.kickc.model.CompileError;
 import dk.camelot64.kickc.model.types.SymbolType;
 import dk.camelot64.kickc.model.values.ConstantBool;
+import dk.camelot64.kickc.model.values.ConstantInteger;
 import dk.camelot64.kickc.model.values.ConstantLiteral;
 
 /** Binary logic and Operator ( x && y ) */
@@ -14,10 +15,7 @@ public class OperatorLogicAnd extends OperatorBinary {
 
    @Override
    public ConstantLiteral calculateLiteral(ConstantLiteral left, ConstantLiteral right) {
-      if(left instanceof ConstantBool && right instanceof ConstantBool) {
-         return new ConstantBool(((ConstantBool) left).getBool() && ((ConstantBool) right).getBool());
-      }
-      throw new CompileError("Calculation not implemented " + left + " " + getOperator() + " " + right);
+      return new ConstantBool(getBool(left) && getBool(right));
    }
 
    @Override
diff --git a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicNot.java b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicNot.java
index b6f27261d..a820cd02c 100644
--- a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicNot.java
+++ b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicNot.java
@@ -16,13 +16,7 @@ public class OperatorLogicNot extends OperatorUnary {
 
    @Override
    public ConstantLiteral calculateLiteral(ConstantLiteral left, ProgramScope scope) {
-      if(left instanceof ConstantEnumerable) {
-         left = new ConstantBool(((ConstantEnumerable) left).getInteger()!=0);
-      }
-      if(left instanceof ConstantBool) {
-         return new ConstantBool(!((ConstantBool) left).getBool() );
-      }
-      throw new CompileError("Calculation not implemented " + getOperator() + " " + left );
+      return new ConstantBool(!getBool(left));
    }
 
    @Override
diff --git a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicOr.java b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicOr.java
index 336be99c0..bf9f9abbe 100644
--- a/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicOr.java
+++ b/src/main/java/dk/camelot64/kickc/model/operators/OperatorLogicOr.java
@@ -1,6 +1,5 @@
 package dk.camelot64.kickc.model.operators;
 
-import dk.camelot64.kickc.model.CompileError;
 import dk.camelot64.kickc.model.types.SymbolType;
 import dk.camelot64.kickc.model.values.ConstantBool;
 import dk.camelot64.kickc.model.values.ConstantLiteral;
@@ -14,10 +13,7 @@ public class OperatorLogicOr extends OperatorBinary {
 
    @Override
    public ConstantLiteral calculateLiteral(ConstantLiteral left, ConstantLiteral right) {
-      if(left instanceof ConstantBool && right instanceof ConstantBool) {
-         return new ConstantBool(((ConstantBool) left).getBool() || ((ConstantBool) right).getBool());
-      }
-      throw new CompileError("Calculation not implemented " + left + " " + getOperator() + " " + right);
+      return new ConstantBool(getBool(left) || getBool(right));
    }
 
    @Override
@@ -25,5 +21,4 @@ public class OperatorLogicOr extends OperatorBinary {
       return SymbolType.BOOLEAN;
    }
 
-
 }
diff --git a/src/test/java/dk/camelot64/kickc/parsing/macros/TestPreprocessor.java b/src/test/java/dk/camelot64/kickc/parsing/macros/TestPreprocessor.java
index 29f4bc763..2158bdac5 100644
--- a/src/test/java/dk/camelot64/kickc/parsing/macros/TestPreprocessor.java
+++ b/src/test/java/dk/camelot64/kickc/parsing/macros/TestPreprocessor.java
@@ -162,6 +162,8 @@ public class TestPreprocessor {
       assertEquals("name:y;", parse("#if defined A\nx;\n#endif\ny;"));
       // Output generated by #elif
       assertEquals("name:y;name:w;", parse("#if 0\nx;\n#elif 1\ny;\n#elif 1\nz;\n#else\nq;\n#endif\nw;"));
+      // Output generated by #if using defined and || operator
+      assertEquals("name:x;name:y;", parse("#define A X\n#if defined(A) || defined(B)\nx;\n#endif\ny;"));
    }
 
    /**