public CodeBlockNode AddNode(IAbstractSyntaxTree lexerNode)
{
switch (lexerNode.Type)
{
case Lexer.TokenType.WhileLoop:
return(AddNode(WhileBlock.Parse(this, lexerNode)));
case Lexer.TokenType.ConditionalSentence:
return(AddNode(ConditionBlockNode.Parse(this, lexerNode)));
case Lexer.TokenType.CodeBlockNode:
return(AddNode(CodeBlockNode.Parse(this, lexerNode)));
case Lexer.TokenType.ForLoop:
return(AddNode(ForLoopNode.Parse(this, lexerNode)));
case Lexer.TokenType.ForEachLoop:
return(AddNode(ForEachNode.Parse(this, lexerNode)));
case Lexer.TokenType.StatementWithEndOfLine:
if (lexerNode.Children.Count == 2)
{
return(AddStatement(lexerNode.Children[0]));
}
else
{
//empty statement a.k.a ";"
return(this);
}
case Lexer.TokenType.UnknownNode:
ErrorCode.InvalidStructure.ReportAndThrow(Parser.GetSequencePoint(lexerNode), "Could not parse as a statement");
return(null); //unreachable
default:
ErrorCode.InvalidStructure.ReportAndThrow(Parser.GetSequencePoint(lexerNode), "Unexpected node {0} in while parsing code block", lexerNode.Type);
return(null); //unreachable
}
}
public static ForEachNode Parse(ContextNode context, IAbstractSyntaxTree lexerNode)
{
//For + LeftParenthesis + ForEachDeclaration + In + Value + RightParenthesis + CodeConstruct),
Contract.Requires(lexerNode.Type == Lexer.TokenType.ForEachLoop);
var instance = new ForEachNode(context, context.Parser.GetSequencePoint(lexerNode));
var collection = ExpressionNode.Parse(context, lexerNode.Children[4]);
if (!collection.IsGettable)
{
ErrorCode.NotAnRValue.ReportAndThrow(collection.SequencePoint, "collection must be a gettable expression");
}
if (collection.ExpressionReturnType.IsTypeless())
{
ErrorCode.InvalidForEachCollection.ReportAndThrow(collection.SequencePoint, "collection must not be a typeless expression");
}
var collectionElementType = collection.ExpressionReturnType.GetEnumerableElementType();
if (collectionElementType == null)
{
ErrorCode.InvalidForEachCollection.ReportAndThrow(collection.SequencePoint, "Cannot iterate over expression type {0}", collection.ExpressionReturnType);
}
var declaration = LoopVariableDeclaration.Parse(context, lexerNode.Children[2], collectionElementType);
if (!collectionElementType.IsAssignableTo(declaration.Variable.VariableType))
{
ErrorCode.TypeMismatch.ReportAndThrow(declaration.SequencePoint, "Cannot assign collection elements of type {0} to {1}", collectionElementType, declaration.Variable.VariableType);
}
instance.collection = collection;
instance.variable = declaration;
instance.body = CodeBlockNode.Parse(instance, lexerNode.Children[6]);
return(instance);
}