public void ConvertEmittedElementsToRealTokenNodes(bool aRecurse)
{
int i = ChildCount;
//
while (i > 0)
{
SymNode child = this[--i];
//
if (child is SymTokenBalancerNodeEmittedElement)
{
SymTokenBalancerNodeEmittedElement emittedElement = (SymTokenBalancerNodeEmittedElement)child;
if (emittedElement.Emit)
{
SymNodeToken replacement = new SymNodeToken(emittedElement.Token);
InsertChild(replacement, child);
}
child.Remove();
}
else if (child is SymTokenBalancerMarkerLevelNode && aRecurse)
{
SymTokenBalancerMarkerLevelNode childLevel = (SymTokenBalancerMarkerLevelNode)child;
childLevel.ConvertEmittedElementsToRealTokenNodes(aRecurse);
}
}
}
protected virtual void PerformEndLevelBehaviour(SymNode aLevel, SymTokenBalancerMatchCriteria aCriteria)
{
#region Example step (11a) from LevelFinished method
//
// We then add the closing bracket to level |1| which means
// that we can attempt to simplify level |2| entirely. This is the
// situation prior to simplification.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [@] [)]
// |
// |2| [(] [*] [)] [+] [(] [*] [)]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ] [E]
//
// aLevel would be the @ node at level |1|.
//
// We remove redundant bracketing from our children, i.e. those on level |2|, not from our own level.
// Our parent takes care of removing this level's redundant bracketing (when it's level is completed)
// or then when an argument separator token is handled.
//
// We must iterate through level |1|'s children to find other level nodes. We check whether each
// child level node can be simplified by checking its children (i.e. our grandchildren).
//
#endregion
if (aCriteria.IsAssociatedBehaviourRemoveRedundantBracketing)
{
int index = 0;
object childLevelNodeObject = aLevel.ChildByType(typeof(SymTokenBalancerMarkerLevelNode), ref index);
while (childLevelNodeObject != null)
{
SymTokenBalancerMarkerLevelNode childLevelNode = (SymTokenBalancerMarkerLevelNode)childLevelNodeObject;
if (childLevelNode.CanBeSubsumed)
{
childLevelNode.Subsume();
}
// Try to find next level node
++index;
childLevelNodeObject = aLevel.ChildByType(typeof(SymTokenBalancerMarkerLevelNode), ref index);
}
}
}
protected void SimplifyLevel(SymTokenBalancerMarkerLevelNode aLevel)
{
System.Diagnostics.Debug.Assert(aLevel.IsRoot == false && aLevel.HasParent);
SymNode parent = aLevel.Parent;
int levelNumber = parent.Depth;
//
int childCount = parent.ChildCount;
while (--childCount >= 0)
{
SymNode possibleLevelNode = parent[childCount];
// We're looking to remove redundant bracketing from either side of the level
// node. First check if we have a level node...
if (possibleLevelNode is SymTokenBalancerMarkerLevelNode)
{
// Then check whether it has a previous and a next node. These should
// be the SymTokenBalancerNodeEmittedElement nodes
if (possibleLevelNode.HasPrevious && possibleLevelNode.HasNext)
{
if (possibleLevelNode.Previous is SymTokenBalancerNodeEmittedElement && possibleLevelNode.Next is SymTokenBalancerNodeEmittedElement)
{
if (LevelCanBeMergedWithParent(possibleLevelNode as SymTokenBalancerMarkerLevelNode))
{
SymTokenBalancerNodeEmittedElement previous = (SymTokenBalancerNodeEmittedElement)possibleLevelNode.Previous;
SymTokenBalancerNodeEmittedElement next = (SymTokenBalancerNodeEmittedElement)possibleLevelNode.Next;
// Insert value node prior to previous node (which is the opening bracket token).
parent.InsertChildrenFrom(possibleLevelNode, previous.Previous);
// Remove the opening bracket token
previous.Remove();
// Remove the level marker token
possibleLevelNode.Remove();
// Remove the closing bracket token.
next.Remove();
}
}
}
}
}
}
protected virtual void LevelStarted(SymToken aToken, SymTokenBalancerMatchCriteria aMatchCriteria)
{
System.Diagnostics.Debug.Write(System.Environment.NewLine + aToken.Value);
// Always store the node element so that we can balance brackets
SymTokenBalancerNodeEmittedElement node = new SymTokenBalancerNodeEmittedElement(aToken, aMatchCriteria);
iTree.CurrentNode.Add(node);
// Store the token (with the level) so we can check for open/close mis-matches
SymTokenBalancerMarkerLevelNode levelNode = new SymTokenBalancerMarkerLevelNode(aMatchCriteria);
iTree.CurrentNode.Add(levelNode);
SymNode oldLevel = iTree.CurrentNode;
SymNode newLevel = levelNode;
NotifyEventLevelStarted(CurrentLevelNumber, oldLevel, newLevel);
iTree.CurrentNode = levelNode;
}
public SymArgumentSubLevel AsArgumentSubLevel(bool aRecurse)
{
SymArgumentSubLevel ret = new SymArgumentSubLevel(this);
//
if (aRecurse)
{
foreach (SymNode child in ret)
{
if (child is SymTokenBalancerMarkerLevelNode)
{
SymTokenBalancerMarkerLevelNode markerNode = (SymTokenBalancerMarkerLevelNode)child;
SymArgumentSubLevel subLevel = markerNode.AsArgumentSubLevel(aRecurse);
ret.InsertChild(subLevel, markerNode);
markerNode.Remove();
}
}
}
//
return(ret);
}
protected void PerformEndLevelBehaviour(SymTokenBalancerMarkerLevelNode aLevel)
{
PerformEndLevelBehaviour(aLevel, aLevel.MatchCriteria);
}
protected virtual void LevelFinished(SymToken aToken, SymTokenBalancerMatchCriteria aMatchCriteria)
{
#region Example
// #define TEST1((( B )+( C ))+(E))
#region Key
// |y| = level y
// [x] = token of value 'x'
// [*] = level marker node
// [@] = (current) level marker node
// [,] = argument node
// [(] = opening level emitted token node
// [)] = closing level emitted token node
#endregion
#region 1) First wave of opening level tokens processed...
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [*]
// |
// |3| [(] [@]
// |
// |4| B
//
#endregion
#region 2) Add closing level token to level |3|, which means that we can now
// attempt to simplify level |4|. Level |4| does not contain any child
// level nodes, so there is nothing to do here.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [@]
// |
// |3| [(] [*] [)]
// |
// |4| [ ] [B] [ ]
//
#endregion
#region 3) Add plus symbol. This obviously becomes a child of the current node,
// i.e. a child of level |2|.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [@]
// |
// |3| [(] [*] [)] [+]
// |
// |4| [ ] [B] [ ]
//
#endregion
#region 4) Start new opening level node on level |3|. The newly added level node
// on level |3| becomes the current node.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [*]
// |
// |3| [(] [*] [)] [+] [(] [@]
// | |
// |4| [ ] [B] [ ]
//
#endregion
#region 5) Add the tokens near the 'C' to level |4|
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [*]
// |
// |3| [(] [*] [)] [+] [(] [@]
// | |
// |4| [ ] [B] [ ] [ ] [C] [ ]
//
#endregion
#region 6) Add closing level token to level |3|, which means that we can now
// attempt to simplify level |4|, this time the [C] branch.
// Since this branch does not contain any sub-level nodes, there is nothing
// to be done and therefore levels |3| and |4| remain unchanged.
// The level node at level |2| becomes the current node.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [@]
// |
// |3| [(] [*] [)] [+] [(] [*] [)]
// | |
// |4| [ ] [B] [ ] [ ] [C] [ ]
//
#endregion
#region 7a) Add closing level token to level |2|, which means that we can now
// attempt to simplify level |3|.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [@] [)]
// |
// |3| [(] [*] [)] [+] [(] [*] [)]
// | |
// |4| [ ] [B] [ ] [ ] [C] [ ]
//
#endregion
#region 7b) We iterate through all the child level nodes of level |3| looking
// to see if any of their children are simple enough to merge up into level
// |3| itself. There are two level nodes in level |3| and both contain
// children that are considered simple enough to merge up. This is because
// they contain only a single non-whitespace node so we can simplify the level by
// merging [B] from level |4| into level |3|. Likewise for [C].
//
// This means that the bracketry on level |3| is redundant since level
// |4| contains two sets of only a single non-whitespace token. Level |4|
// is therefore entirely removed.
//
// The node at level |1| becomes the current node now.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [@]
// |
// |2| [(] [*] [)]
// |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ]
//
#endregion
#region 8) Add the plus symbol to level |2|. Then we start a new level
// as a result of adding the opening bracket prior to 'E.'
// This new level node at level |2| now becomes the current node.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [*] [)] [+] [(] [@]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ]
//
#endregion
#region 9) Now add the 'E' token to level |3|.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [*]
// |
// |2| [(] [*] [)] [+] [(] [@]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ] [E]
#endregion
#region 10) We then add the closing bracket to level |2| which means
// that we can attempt to simplify level |3|'s 'E' branch. There's nothing
// to do though, since it doesn't contain any child level nodes.
// The level node at level |1| again becomes current.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [@]
// |
// |2| [(] [*] [)] [+] [(] [*] [)]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ] [E]
#endregion
#region 11a) We then add the closing bracket to level |1| which means
// that we can attempt to simplify level |2| entirely. This is the
// situation prior to simplification.
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [@] [)]
// |
// |2| [(] [*] [)] [+] [(] [*] [)]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ] [E]
#endregion
#region 11b) The two level nodes have been taged as *1 and *2 to make it
// easier to explain the process. First we attempt to simplify level *1.
// However, since its children consist of more than a single non-whitespace
// token, we cannot make level |3|'s " B + C " branch as a replacement
// for the bracket *1 tokens. Therefore this remains unchanged
//
//
// |0| [ROOT]
// |
// |1| [TEST] [(] [@] [)]
// |
// |2| [(] [*1] [)] [+] [(] [*2] [)]
// | |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ] [E]
#endregion
#region 11c) The level *2 node, however, contains only a single non-whitespace
// child token, so it can be simplified. The level *2 node is replaced by
// its child (E).
//
// The final tree looks like this, with the root as the current node once more:
//
//
// |0| [@ROOT@]
// |
// |1| [TEST] [(] [*] [)]
// |
// |2| [(] [*] [)] [+] [E]
// |
// |3| [ ] [B] [ ] [+] [ ] [C] [ ]
#endregion
#endregion
System.Diagnostics.Debug.Write(aToken.Value);
System.Diagnostics.Debug.WriteLine(" ");
// First of all, check if the current node has a parent. If we're at the root
// node and we see a closing token, then we've got an imbalanced stack.
if (iTree.CurrentNode.IsRoot)
{
NotifyEventLevelsImbalanced();
}
else
{
// We expect the parent to be a level node
System.Diagnostics.Debug.Assert(iTree.CurrentNode is SymTokenBalancerMarkerLevelNode);
// Notify that we're about to change levels
SymTokenBalancerMarkerLevelNode currentLevel = (SymTokenBalancerMarkerLevelNode)iTree.CurrentNode;
SymNode newLevel = currentLevel.Parent;
// The new level should not be null in this case
System.Diagnostics.Debug.Assert(newLevel != null);
// Check whether the closing token type is the same type as was used to start
// the level. E.g. for this case is "([ANDMORE)]" which has a mis-match
// between the opening and closing braces on each level. We can't simplify this
// during the 'end level behaviour' stage.
bool levelsBalanced = currentLevel.MatchCriteria.DiametricToken.Equals(aToken);
// Switch levels
iTree.CurrentNode = newLevel;
// We have to refetch up-to-date match info, since we've changed levels, and the match
// info that was used to enter this method is associated with the previous level
// (not the new level number, which is now one less).
SymTokenBalancerMatchCriteria matchCriteria;
if (IsClosingTokenMatch(aToken, out matchCriteria, CurrentLevelNumber) == false)
{
matchCriteria = aMatchCriteria;
}
// Always store the node element so that we can balance brackets
SymTokenBalancerNodeEmittedElement node = new SymTokenBalancerNodeEmittedElement(aToken, matchCriteria);
iTree.CurrentNode.Add(node);
// We have finished the current level. E.g. see step 6. Need to simplify level |2|, where possible.
PerformEndLevelBehaviour(currentLevel);
if (levelsBalanced)
{
// Notify that we've finished some level
NotifyEventLevelFinished(CurrentLevelNumber, currentLevel, newLevel);
}
else
{
// Imbalance
NotifyEventLevelsImbalanced();
}
}
}
protected bool LevelCanBeMergedWithParent(SymTokenBalancerMarkerLevelNode aLevelNode)
{
#region Example
// We can replace the opening bracket, the level marker and the closing bracket
// with the level marker's child.
//
// E.g.
// ( = opening bracket
// * = level marker
// ) = closing bracket
// V = 'real' node value
//
// This:
//
// ( -- * -- )
// |
// V
//
// Can become:
//
// V
//
//
// Or this:
//
// ( -- * -- )
// |
// [ -- * -- ]
// |
// V
//
// Can become:
//
// [ -- * -- ]
// |
// V
//
#endregion
System.Diagnostics.Debug.Assert(aLevelNode.HasPrevious && aLevelNode.HasNext);
System.Diagnostics.Debug.Assert(aLevelNode.Previous is SymTokenBalancerNodeEmittedElement && aLevelNode.Next is SymTokenBalancerNodeEmittedElement);
//
bool ret = false;
//
SymTokenBalancerNodeEmittedElement previous = (SymTokenBalancerNodeEmittedElement)aLevelNode.Previous;
SymTokenBalancerNodeEmittedElement next = (SymTokenBalancerNodeEmittedElement)aLevelNode.Next;
// We should be able to remove these brackets, providing they are diametrically oposites.
SymTokenBalancerMatchCriteria matchInfo;
if (IsOpeningTokenMatch(previous.Token, out matchInfo, CurrentLevelNumber))
{
// We've now got the match info for this opening token. We can compare the
// match info's diametric token against the closing token to check that they
// really are equal and oposite.
if (matchInfo.DiametricToken.Equals(next.Token))
{
// Check whether the children are suitable for coalescing
int grandChildCount = aLevelNode.ChildCount;
int numberOfWhiteSpaceGrandChildren = CountTokenByType(aLevelNode, SymToken.TClass.EClassWhiteSpace);
int nonWhiteSpaceGrandChildrenCount = grandChildCount - numberOfWhiteSpaceGrandChildren;
if (nonWhiteSpaceGrandChildrenCount == 1)
{
// If there is just a single non-whitespace token then we are able to
// coalesce this branch
ret = true;
}
else if (nonWhiteSpaceGrandChildrenCount == 3)
{
// Branch contains several non-whitespace children. Must check further
// to see if they are simply bracketed regions themselves
object levelObject = aLevelNode.ChildByType(typeof(SymTokenBalancerMarkerLevelNode));
if (levelObject != null)
{
SymTokenBalancerMarkerLevelNode childLevel = (SymTokenBalancerMarkerLevelNode)levelObject;
//
if (childLevel.HasPrevious && childLevel.HasNext)
{
ret = (childLevel.Previous is SymTokenBalancerNodeEmittedElement && childLevel.Next is SymTokenBalancerNodeEmittedElement);
}
}
else
{
ret = true;
}
}
}
}
//
return(ret);
}