/// <summary>
/// Make a tree from a list of nodes. The first element in the
/// array is the root. If the root is null, then the tree is
/// a simple list not a tree. Handles null children nodes correctly.
/// For example, build(a, b, null, c) yields tree (a b c). build(null,a,b)
/// yields tree (nil a b).
/// </summary>
/// <param name="nodes">List of Nodes.</param>
/// <returns>AST Node tree.</returns>
public virtual AST make(params AST[] nodes)
{
if (nodes == null || nodes.Length == 0)
{
return(null);
}
AST root = nodes[0];
AST tail = null;
if (root != null)
{
root.setFirstChild(null); // don't leave any old pointers set
}
// link in children;
for (int i = 1; i < nodes.Length; i++)
{
if (nodes[i] == null)
{
continue;
}
// ignore null nodes
if (root == null)
{
// Set the root and set it up for a flat list
root = (tail = nodes[i]);
}
else if (tail == null)
{
root.setFirstChild(nodes[i]);
tail = root.getFirstChild();
}
else
{
tail.setNextSibling(nodes[i]);
tail = tail.getNextSibling();
}
// Chase tail to last sibling
while (tail.getNextSibling() != null)
{
tail = tail.getNextSibling();
}
}
return(root);
}
public void visit(AST node)
{
// Flatten this level of the tree if it has no children
bool flatten = /*true*/ false;
AST node2;
for (node2 = node; node2 != null; node2 = node2.getNextSibling())
{
if (node2.getFirstChild() != null)
{
flatten = false;
break;
}
}
for (node2 = node; node2 != null; node2 = node2.getNextSibling())
{
if (!flatten || node2 == node)
{
tabs();
}
if (node2.getText() == null)
{
Console.Out.Write("nil");
}
else
{
Console.Out.Write(node2.getText());
}
Console.Out.Write(" [" + node2.Type + "] ");
if (flatten)
{
Console.Out.Write(" ");
}
else
{
Console.Out.WriteLine("");
}
if (node2.getFirstChild() != null)
{
level++;
visit(node2.getFirstChild());
level--;
}
}
if (flatten)
{
Console.Out.WriteLine("");
}
}
/// <summary>
/// Duplicate AST Node tree rooted at specified AST node and all of it's siblings.
/// </summary>
/// <param name="t">Root of AST Node tree.</param>
/// <returns>Root node of new AST Node tree (or null if <c>t</c> is null).</returns>
public virtual AST dupList(AST t)
{
AST result = dupTree(t); // if t == null, then result==null
AST nt = result;
while (t != null)
{
// for each sibling of the root
t = t.getNextSibling();
nt.setNextSibling(dupTree(t)); // dup each subtree, building new tree
nt = nt.getNextSibling();
}
return(result);
}
/*Print out a child-sibling tree in LISP notation */
public virtual string ToStringList()
{
AST t = this;
string ts = "";
if (t.getFirstChild() != null)
{
ts += " (";
}
ts += " " + this.ToString();
if (t.getFirstChild() != null)
{
ts += ((BaseAST)t.getFirstChild()).ToStringList();
}
if (t.getFirstChild() != null)
{
ts += " )";
}
if (t.getNextSibling() != null)
{
ts += ((BaseAST)t.getNextSibling()).ToStringList();
}
return(ts);
}
public virtual void xmlSerialize(TextWriter outWriter)
{
// print out this node and all siblings
for (AST node = this; node != null; node = node.getNextSibling())
{
if (node.getFirstChild() == null)
{
// print guts (class name, attributes)
((BaseAST)node).xmlSerializeNode(outWriter);
}
else
{
((BaseAST)node).xmlSerializeRootOpen(outWriter);
// print children
((BaseAST)node.getFirstChild()).xmlSerialize(outWriter);
// print end tag
((BaseAST)node).xmlSerializeRootClose(outWriter);
}
}
}
/*Is 'sub' a subtree of this list?
* The siblings of the root are NOT ignored.
*/
public virtual bool EqualsListPartial(AST sub)
{
AST sibling;
// the empty tree is always a subset of any tree.
if (sub == null)
{
return(true);
}
// Otherwise, start walking sibling lists. First mismatch, return false.
for (sibling = this; sibling != null && sub != null; sibling = sibling.getNextSibling(), sub = sub.getNextSibling())
{
// as a quick optimization, check roots first.
if (!sibling.Equals(sub))
{
return(false);
}
// if roots match, do partial list match test on children.
if (sibling.getFirstChild() != null)
{
if (!sibling.getFirstChild().EqualsListPartial(sub.getFirstChild()))
{
return(false);
}
}
}
if (sibling == null && sub != null)
{
// nothing left to match in this tree, but subtree has more
return(false);
}
// either both are null or sibling has more, but subtree doesn't
return(true);
}
/*Is t an exact structural and equals() match of this tree. The
* 'this' reference is considered the start of a sibling list.
*/
public virtual bool EqualsList(AST t)
{
AST sibling;
// the empty tree is not a match of any non-null tree.
if (t == null)
{
return(false);
}
// Otherwise, start walking sibling lists. First mismatch, return false.
for (sibling = this; sibling != null && t != null; sibling = sibling.getNextSibling(), t = t.getNextSibling())
{
// as a quick optimization, check roots first.
if (!sibling.Equals(t))
{
return(false);
}
// if roots match, do full list match test on children.
if (sibling.getFirstChild() != null)
{
if (!sibling.getFirstChild().EqualsList(t.getFirstChild()))
{
return(false);
}
}
else if (t.getFirstChild() != null)
{
return(false);
}
}
if (sibling == null && t == null)
{
return(true);
}
// one sibling list has more than the other
return(false);
}