private Expression GenerateConditional(Expression test, Expression expr1, Expression expr2, int errorPos)
{
if (test.Type != typeof(bool))
{
throw ParseError(errorPos, Res.FirstExprMustBeBool);
}
return EqualizeTypesAndCombine(expr1, expr2, errorPos, (e1, e2) => Expression.Condition(test, e1, e2));
}