Added/Corrected Documentation

MathPad/MPFunction.h

@@ -26,7 +26,7 @@
 
 
 
-@class MPFunction, MPExpression, MPRangePath, MPFunctionTerm;
+@class MPFunction, MPExpression, MPRangePath;
 @protocol MPExpressionElement;
 
 
@@ -119,7 +119,7 @@
 
 /*!
     @method     childAtIndex:
-    @brief      Returns the child at the given index.
+    @brief      Returns the child at the specified index.
  
     @discussion The ordering of children is determined by the order of the
                 children returned from the @c -childrenAccessors method.
@@ -243,9 +243,29 @@
 
 
 #pragma mark Evaluating Functions
+/*!
+ @methodgroup Evaluating Functions
+ */
 
 
-- (BOOL)expectsVariableDefinitionInChildAtIndex:(NSUInteger)index;
+/*!
+    @method     expectsVariableDefinitionInChildAtIndex:
+    @brief      Returns whether the child at @c anIndex is supposed to contain a
+                variable definition.
+ 
+    @discussion This method is automatically called during expression parsing.
+                You can override this method to opt into the default behaviour.
+                If you override this method you do not need to call super.
+                
+                The default implementation just returns @c NO for every index.
+ 
+    @param      anIndex
+                The index of the child to check.
+ 
+    @return     @c YES if the child at @c anIndex is supposed to contain a
+                variable definition, @c NO otherwise.
+ */
+- (BOOL)expectsVariableDefinitionInChildAtIndex:(NSUInteger)anIndex;
 
 @end
 
@@ -263,7 +283,9 @@
 @interface MPFunction (MPSubclassOverride)
 
 /* In Addition to the methods listed below MPFunction subclasses should also
- * override the NSObject methods -description and -hash.
+ * override the NSObject method -description.
+ * Also -expectsVariabledefinitionInChildAtIndex: can be overridden if one of the
+ * children should contain a variable definition.
  */
 
 #pragma mark Working With the Expression Tree
@@ -291,6 +313,18 @@
  @methodgroup Evaluating Functions
  */
 
+
+/*!
+    @method     functionTermClass
+    @brief      Returns the class that represents the receiver's evaluation
+                behaviour.
+ 
+    @discussion The class returned must be a subclass of @c MPFunctionTerm. That
+                class must not implement a custom initializer.
+ 
+    @return     The @c MPFunctionTerm subclass that can evaluate instances of the
+                receiver's class.
+ */
 - (Class)functionTermClass;
 
 @end