public override AstNode Visit(IsExpression node)
{
// Begin the node.
builder.BeginNode(node);
// Get the target type and value.
//Expression cmp = node.GetCompare();
Expression value = node.GetValue();
// Visit them.
//target.Accept(this);
value.Accept(this);
// Perform coercion.
IChelaType valueType = value.GetNodeType();
IChelaType coercionType = node.GetCoercionType();
if(valueType != coercionType)
Cast(node, value.GetNodeValue(), valueType, coercionType);
// Perform the type comparison.
IChelaType targetType = node.GetTargetType();
if(targetType != valueType)
{
builder.CreateIsA(targetType);
}
else
{
builder.CreatePop();
builder.CreateLoadBool(true);
}
return builder.EndNode();
}
public override AstNode Visit(IsExpression node)
{
// Get the target type and value.
Expression compare = node.GetCompare();
Expression value = node.GetValue();
// Visit them.
compare.Accept(this);
value.Accept(this);
// The value must be a reference.
IChelaType valueType = value.GetNodeType();
// De-ref the value.
valueType = DeReferenceType(valueType);
valueType = DeReferenceType(valueType);
if(valueType.IsPassedByReference())
node.SetCoercionType(ReferenceType.Create(valueType));
else if(valueType.IsFirstClass() || valueType.IsPlaceHolderType())
node.SetCoercionType(valueType);
else
Error(node, "expected an object instead of {0}", valueType.GetDisplayName());
// Get the target type.
IChelaType targetType = compare.GetNodeType();
targetType = ExtractActualType(compare, targetType);
// Store the target type.
node.SetTargetType(targetType);
// Set the node type.
node.SetNodeType(ChelaType.GetBoolType());
return node;
}
