refactoring

src/com/bytezone/diskbrowser/visicalc/Abs.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Abs extends Function
 {
-  private final Value source;
-
   Abs (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ABS(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Acos.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Acos extends Function
 {
-  private final Value source;
-
   Acos (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ACOS(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Asin.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Asin extends Function
 {
-  private final Value source;
-
   Asin (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ASIN(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Atan.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Atan extends Function
 {
-  private final Value source;
-
   Atan (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ATAN(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Average.java

@@ -4,7 +4,6 @@ import com.bytezone.diskbrowser.visicalc.Cell.CellType;
 
 public class Average extends Function
 {
-  private final ValueList list;
   private final boolean isRange;      // may affect how the count is done
 
   public Average (Cell cell, String text)

src/com/bytezone/diskbrowser/visicalc/Cell.java

@@ -33,6 +33,16 @@ class Cell extends AbstractValue implements Comparable<Cell>
     isVolatile = false;
   }
 
+  Function getFunction (String text)
+  {
+    return parent.getFunction (this, text);
+  }
+
+  Value getExpressionValue (String text)
+  {
+    return new Expression (this, text).reduce ();
+  }
+
   boolean isCellType (CellType cellType)
   {
     return this.cellType == cellType;
@@ -106,7 +116,7 @@ class Cell extends AbstractValue implements Comparable<Cell>
       try
       {
         expressionText = command;
-        value = new Expression (parent, this, expressionText).reduce ();
+        value = new Expression (this, expressionText).reduce ();
         cellType = CellType.VALUE;
         isVolatile = true;
       }

src/com/bytezone/diskbrowser/visicalc/Choose.java

@@ -2,23 +2,17 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Choose extends Function
 {
-  private final String sourceText;
-  private final String rangeText;
-
-  private final Value source;
-  private final Range range;
-
   Choose (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@CHOOSE(") : text;
 
-    sourceText = Expression.getParameter (functionText);
-    source = new Expression (parent, cell, sourceText).reduce ();
+    String sourceText = Expression.getParameter (functionText);
+    source = cell.getExpressionValue (sourceText);
     values.add (source);
 
-    rangeText = functionText.substring (sourceText.length () + 1);
+    String rangeText = functionText.substring (sourceText.length () + 1);
     range = new Range (parent, cell, rangeText);
   }
 

src/com/bytezone/diskbrowser/visicalc/Condition.java

@@ -29,13 +29,13 @@ class Condition extends AbstractValue implements Iterable<Value>
       if (pos > 0)
       {
         conditionText = text.substring (0, pos);
-        conditionExpression = new Expression (parent, cell, conditionText);
+        conditionExpression = new Expression (cell, conditionText);
         values.add (conditionExpression);
 
         comparator = comp;
 
         valueText = text.substring (pos + comp.length ());
-        valueExpression = new Expression (parent, cell, valueText);
+        valueExpression = new Expression (cell, valueText);
         values.add (valueExpression);
         break;
       }
@@ -46,13 +46,13 @@ class Condition extends AbstractValue implements Iterable<Value>
       if (text.startsWith ("@"))
       {
         conditionText = text;
-        conditionExpression = new Expression (parent, cell, text);
+        conditionExpression = new Expression (cell, text);
         values.add (conditionExpression);
 
         comparator = "=";
 
         valueText = "1";
-        valueExpression = new Expression (parent, cell, valueText);
+        valueExpression = new Expression (cell, valueText);
         values.add (valueExpression);
       }
       else

src/com/bytezone/diskbrowser/visicalc/Cos.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Cos extends Function
 {
-  private final Value source;
-
   Cos (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@COS(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Count.java

@@ -4,7 +4,6 @@ import com.bytezone.diskbrowser.visicalc.Cell.CellType;
 
 class Count extends Function
 {
-  private final ValueList list;
   private final boolean isRange;
 
   public Count (Cell cell, String text)

src/com/bytezone/diskbrowser/visicalc/Exp.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Exp extends Function
 {
-  private final Value source;
-
   Exp (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@EXP(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Expression.java

@@ -35,11 +35,12 @@ class Expression extends AbstractValue implements Iterable<Value>
 
   private final String text;
 
-  public Expression (Sheet parent, Cell cell, String text)
+  public Expression (Cell cell, String text)
   {
     super ("Exp");
     this.cell = cell;
     this.text = text;
+    Sheet parent = cell.getParent ();
 
     String line = balanceBrackets (text);   // add trailing right brackets if necessary
 
@@ -66,13 +67,13 @@ class Expression extends AbstractValue implements Iterable<Value>
         case '@':                                           // function
           String functionText = getFunctionCall (line.substring (ptr));
           ptr += functionText.length ();
-          values.add (parent.getFunction (cell, functionText));
+          values.add (cell.getFunction (functionText));
           break;
 
         case '(':                                           // parentheses block
           String bracketText = getBalancedText (line.substring (ptr));
           ptr += bracketText.length ();
-          values.add (new Expression (parent, cell,
+          values.add (new Expression (cell,
               bracketText.substring (1, bracketText.length () - 1)));
           break;
 

src/com/bytezone/diskbrowser/visicalc/Function.java

@@ -16,9 +16,14 @@ abstract class Function extends AbstractValue implements Iterable<Value>
   protected String functionText;
   protected String fullText;
 
+  protected Value source;
+  protected ValueList list;
+  protected Range range;
+
   Function (Cell cell, String text)
   {
     super ("Function");
+
     this.parent = cell.getParent ();
     this.cell = cell;
     fullText = text;

src/com/bytezone/diskbrowser/visicalc/If.java

@@ -25,10 +25,10 @@ class If extends Function
     condition = new Condition (parent, cell, conditionText);
     values.add (condition);
 
-    expTrue = new Expression (parent, cell, textTrue);
+    expTrue = new Expression (cell, textTrue);
     values.add (expTrue);
 
-    expFalse = new Expression (parent, cell, textFalse);
+    expFalse = new Expression (cell, textFalse);
     values.add (expFalse);
   }
 

src/com/bytezone/diskbrowser/visicalc/Int.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Int extends Function
 {
-  private final Value source;
-
   Int (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@INT(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/IsError.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 class IsError extends Function
 {
-  private final Value source;
-
   public IsError (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ISERROR(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/IsNa.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class IsNa extends Function
 {
-  private final Value source;
-
   IsNa (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@ISNA(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Ln.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Ln extends Function
 {
-  private final Value source;
-
   Ln (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@LN(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Log10.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Log10 extends Function
 {
-  private final Value source;
-
   Log10 (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@LOG10(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Lookup.java

@@ -2,23 +2,17 @@ package com.bytezone.diskbrowser.visicalc;
 
 class Lookup extends Function
 {
-  private final String sourceText;
-  private final String rangeText;
-
-  private final Value source;
-  private final Range range;
-
   public Lookup (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@LOOKUP(") : text;
 
-    sourceText = Expression.getParameter (functionText);
-    source = new Expression (parent, cell, sourceText).reduce ();
+    String sourceText = Expression.getParameter (functionText);
+    source = cell.getExpressionValue (sourceText);
     values.add (source);
 
-    rangeText = functionText.substring (sourceText.length () + 1);
+    String rangeText = functionText.substring (sourceText.length () + 1);
     range = new Range (parent, cell, rangeText);
   }
 
@@ -72,7 +66,4 @@ class Lookup extends Function
       }
     }
   }
-
-  // @LOOKUP(B8,F3...F16)
-  // @LOOKUP(.2*K8+K7,F3...F16)
 }

src/com/bytezone/diskbrowser/visicalc/Max.java

@@ -2,8 +2,6 @@ package com.bytezone.diskbrowser.visicalc;
 
 class Max extends Function
 {
-  private final ValueList list;
-
   public Max (Cell cell, String text)
   {
     super (cell, text);

src/com/bytezone/diskbrowser/visicalc/Min.java

@@ -2,8 +2,6 @@ package com.bytezone.diskbrowser.visicalc;
 
 class Min extends Function
 {
-  private final ValueList list;
-
   public Min (Cell cell, String text)
   {
     super (cell, text);

src/com/bytezone/diskbrowser/visicalc/Npv.java

@@ -4,23 +4,17 @@ import com.bytezone.diskbrowser.visicalc.Cell.CellType;
 
 public class Npv extends Function
 {
-  private final String sourceText;
-  private final String rangeText;
-
-  private final Value source;
-  private final Range range;
-
   Npv (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@NPV(") : text;
 
-    sourceText = Expression.getParameter (functionText);
-    source = new Expression (parent, cell, sourceText).reduce ();
+    String sourceText = Expression.getParameter (functionText);
+    source = cell.getExpressionValue (sourceText);
     values.add (source);
 
-    rangeText = functionText.substring (sourceText.length () + 1);
+    String rangeText = functionText.substring (sourceText.length () + 1);
     range = new Range (parent, cell, rangeText);
   }
 

src/com/bytezone/diskbrowser/visicalc/Sheet.java

@@ -493,24 +493,16 @@ public class Sheet
 
   Function getFunction (Cell cell, String text)
   {
-    if (text.charAt (0) != '@')
-    {
-      System.out.printf ("Unknown function: [%s]%n", text);
-      return new Error (cell, "@ERROR");
-    }
-
-    String functionName = "";
     int functionId = -1;
     for (int i = 0; i < Function.functionList.length; i++)
       if (text.startsWith (Function.functionList[i]))
       {
         functionId = i;
         functionTotals[i]++;
-        functionName = Function.functionList[i];
         break;
       }
 
-    if (functionName.isEmpty ())
+    if (functionId < 0)
     {
       System.out.printf ("Unknown function: [%s]%n", text);
       return new Error (cell, "@ERROR");
@@ -609,7 +601,7 @@ public class Sheet
         return new True (cell, text);
 
       default:
-        System.out.printf ("Unknown function: [%s]%n", text);
+        System.out.printf ("Unknown function ID: %d%n", functionId);
         return new Error (cell, "@ERROR");
     }
   }

src/com/bytezone/diskbrowser/visicalc/Sin.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Sin extends Function
 {
-  private final Value source;
-
   Sin (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@SIN(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Sqrt.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Sqrt extends Function
 {
-  private final Value source;
-
   Sqrt (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@SQRT(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/Sum.java

@@ -2,8 +2,6 @@ package com.bytezone.diskbrowser.visicalc;
 
 class Sum extends Function
 {
-  private final ValueList list;
-
   public Sum (Cell cell, String text)
   {
     super (cell, text);

src/com/bytezone/diskbrowser/visicalc/Tan.java

@@ -2,15 +2,13 @@ package com.bytezone.diskbrowser.visicalc;
 
 public class Tan extends Function
 {
-  private final Value source;
-
   Tan (Cell cell, String text)
   {
     super (cell, text);
 
     assert text.startsWith ("@TAN(") : text;
 
-    source = new Expression (parent, cell, functionText).reduce ();
+    source = cell.getExpressionValue (functionText);
     values.add (source);
   }
 

src/com/bytezone/diskbrowser/visicalc/ValueList.java

@@ -21,7 +21,7 @@ public class ValueList implements Iterable<Value>
         for (Address address : new Range (parent, cell, parameter))
           values.add (parent.getCell (address));
       else
-        values.add (new Expression (parent, cell, parameter).reduce ());
+        values.add (new Expression (cell, parameter).reduce ());
 
       if (remainder.length () == parameter.length ())
         break;