public Expr OnParseNew()
{
var tokenIt = this._parser.TokenIt;
var initiatorToken = tokenIt.NextToken;
var expr = new NewExpr();
// <codeNew>
tokenIt.Expect(Tokens.New);
var typeName = tokenIt.ExpectId();
// Keep parsing to capture full name.
// e.g new App.Core.User()
while (tokenIt.NextToken.Token == Tokens.Dot)
{
tokenIt.Advance();
var name = tokenIt.ExpectId();
typeName += "." + name;
if (tokenIt.IsEndOfStmtOrBlock())
break;
}
expr.TypeName = typeName;
expr.ParamListExpressions = new List<Expr>();
expr.ParamList = new List<object>();
this._parser.State.FunctionCall++;
this._parser.ParseParameters(expr, true, false);
this._parser.State.FunctionCall--;
// </codeNew>
this._parser.SetupContext(expr, initiatorToken);
return expr;
}
/// <summary>
/// Creates new instance of the type.
/// </summary>
/// <returns></returns>
public object VisitNew(NewExpr expr)
{
object[] constructorArgs = null;
var paramListExprs = expr.ParamListExpressions;
if (paramListExprs != null && paramListExprs.Count > 0)
{
expr.ParamList = new List<object>();
ParamHelper.ResolveNonNamedParameters(paramListExprs, expr.ParamList, this);
constructorArgs = expr.ParamList.ToArray();
}
// CASE 1: Built in basic system types ( string, date, time, etc )
if (LTypesLookup.IsBasicTypeShortName(expr.TypeName))
{
// TODO: Move this check to Semacts later
var langType = LTypesLookup.GetLType(expr.TypeName);
var methods = this.Ctx.Methods.Get(langType);
var canCreate = methods.CanCreateFromArgs(constructorArgs);
if (!canCreate)
throw ExceptionHelper.BuildRunTimeException(expr, "Can not create " + expr.TypeName + " from parameters");
// Allow built in type methods to create it.
var result = methods.CreateFromArgs(constructorArgs);
return result;
}
// CASE 2: Custom types e.g. custom classes.
var hostLangArgs = LangTypeHelper.ConvertToArrayOfHostLangValues(constructorArgs);
var instance = this.Ctx.Types.Create(expr.TypeName, hostLangArgs);
var obj = LangTypeHelper.ConvertToLangClass(instance);
return obj;
}
/// <summary>
/// Check new expressions.
/// </summary>
/// <param name="semActs">The semantic analyser</param>
/// <param name="exp">The newexpression</param>
private SemanticCheckResult CheckNewExpression(SemActs semActs, NewExpr exp)
{
var typeName = exp.TypeName;
// 1. Check # params to Date
if (string.Compare(typeName, "Date", StringComparison.InvariantCultureIgnoreCase) == 0)
{
if (!DateTimeTypeHelper.CanCreateDateFrom(exp.ParamListExpressions.Count))
return AddError("Unexpected number of inputs when creating date", exp);
}
// 2. Check # params to Time
else if (string.Compare(typeName, "Time", StringComparison.InvariantCultureIgnoreCase) == 0)
{
if (!DateTimeTypeHelper.CanCreateTimeFrom(exp.ParamListExpressions.Count))
return AddError("Unexpected number of inputs when creating time", exp);
}
return SemanticCheckResult.Valid;
}
/// <summary>
/// Visits the function call expression tree
/// </summary>
/// <param name="exp"></param>
public object VisitNew(NewExpr exp)
{
return null;
}