public Node Instantiate(string guid)
{
var parserNode = ParserNodes.FirstOrDefault(p => p.Guid == guid);
if (parserNode == null)
{
var error = new BuildError {
Message = $"Could not find a node with GUID: {guid}."
};
Errors.Add(error);
return(null);
}
// Uses a depth first loop instead of recursion to avoid potential stack overflows.
var root = parserNode.CreateInstance(TypeDefMap, Errors);
var n = new InstantiationNode {
Instance = root, Parser = parserNode
};
var open = new Stack <InstantiationNode>();
open.Push(n);
while (open.Count > 0)
{
var next = open.Pop();
var children = next.Parser.IsDerivedFromTypeDef
? TypeDefMap[next.Parser.Tag].Children
: next.Parser.Children;
foreach (var parserChild in children)
{
var instance = parserChild.CreateInstance(TypeDefMap, Errors);
if (instance == null)
{
continue;
}
var c = new InstantiationNode {
Instance = instance, Parser = parserChild
};
if (next.Instance.Children == null)
{
next.Instance.Children = new List <Node>();
}
next.Instance.Children.Add(instance);
open.Push(c);
}
}
foreach (var node in root.DepthFirstIterate())
{
node?.Initialize();
}
return(root);
}
private ExpressionNode Instantiation()
{
ExpressionNode itsAST = null; // in case there is a syntactic error
SourceCodePosition itsPos = _currentToken.SourcePosition;
Accept(Token.TokenType.New);
if (Array.Exists(_typeFirstSet, e => e == _currentToken.Type && e != Token.TokenType.Identifier))
{
TypeNode itsType = ValueType();
ExpressionNode itsSize = ArrayExpression();
ArrayTypeNode itsArray = new ArrayTypeNode(itsType, itsSize, itsPos);
itsAST = new InstantiationNode(itsArray, itsSize, itsPos);
}
else
{
IdentifierNode itsName = new IdentifierNode(_currentToken);
Accept(Token.TokenType.Identifier);
ClassTypeNode itsType = new ClassTypeNode(itsName, _currentToken.SourcePosition);
if (_currentToken.Type == Token.TokenType.LeftBracket)
{
ExpressionNode itsSize = ArrayExpression();
ArrayTypeNode itsArray = new ArrayTypeNode(itsType, itsSize, itsPos);
itsAST = new InstantiationNode(itsArray, itsSize, itsPos);
}
else if (_currentToken.Type == Token.TokenType.LeftParen)
{
itsAST = new InstantiationNode(itsType, Call(itsName), itsPos);
}
else
{
Error("Expected leftBracket or leftParen");
}
}
return(itsAST);
}
public object Visit(InstantiationNode n, object o)
{
Append($"new ");
if (n.Type is ArrayTypeNode)
{
// if the type is an array, visit the type of that array to enclose the expression in brackets
((ArrayTypeNode)n.Type).Type.Accept(this, null);
Append("[");
n.Expression.Accept(this, null);
Append("]");
}
else
{
n.Type.Accept(this, null);
n.Expression.Accept(this, null);
}
return(null);
}
public object Visit(InstantiationNode n, object o)
{
return(null);
}
