/// <summary>
/// Visit a parse tree produced by <see cref="algoParser.stat_list_add"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitStat_list_add([NotNull] algoParser.Stat_list_addContext context)
{
return(VisitChildren(context));
}
//Adding an item to a list.
public override object VisitStat_list_add([NotNull] algoParser.Stat_list_addContext context)
{
//Evaluate the value to be added to the list.
AlgoValue toAdd = (AlgoValue)VisitExpr(context.expr()[0]);
//Get the list variable from the identifier and particle.
AlgoValue listVar = Particles.ParseParticleBlock(this, context, context.IDENTIFIER(), context.particle());
if (listVar == null)
{
Error.Fatal(context, "No list value returned to add to from particle block.");
return(null);
}
//Check the type is actually a list.
if (listVar.Type != AlgoValueType.List)
{
Error.Fatal(context, "Variable given is not list, so can't remove an item from it.");
return(null);
}
//Add a value to the list, either at a specific index or to the end.
List <AlgoValue> toReturn = (List <AlgoValue>)listVar.Value;
if (context.AT_SYM() != null)
{
//Evaluate the index.
AlgoValue index = (AlgoValue)VisitExpr(context.expr()[1]);
//Is it an integer?
if (index.Type == AlgoValueType.Integer)
{
Error.Fatal(context, "The index supplied to insert at was not an integer.");
return(null);
}
//Is it 0 or above?
if ((BigInteger)index.Value < 0)
{
Error.Fatal(context, "The index supplied is below zero, out of range.");
return(null);
}
//Is the index greater than the length of the list?
if ((BigInteger)index.Value > ((List <AlgoValue>)listVar.Value).Count || (BigInteger)index.Value > int.MaxValue)
{
Error.Fatal(context, "The index supplied was out of range (too large).");
return(null);
}
//Insert.
toReturn.Insert(int.Parse(((BigInteger)index.Value).ToString()), toAdd);
}
else
{
toReturn.Add(toAdd);
}
//Set the variable via. reference (TEST ME!).
listVar.Value = toReturn;
return(null);
}
/// <summary>
/// Exit a parse tree produced by <see cref="algoParser.stat_list_add"/>.
/// <para>The default implementation does nothing.</para>
/// </summary>
/// <param name="context">The parse tree.</param>
public virtual void ExitStat_list_add([NotNull] algoParser.Stat_list_addContext context)
{
}