public override object VisitDecrementExpr([NotNull] CalculatorParser.DecrementExprContext context)
{
var varName = context.Id().Accept(this) as string;
object oldValue = GetValue(context.Id());
var newValue = (int)oldValue - 1;
var node = context.children[0] as ITerminalNode;
m_stack.Set(varName, newValue);
// Pre-decrement
if (node.Symbol.Type == CalculatorParser.Decrement)
{
return(GetValue(context.Id()));
}
// Post-decrement
else
{
return(oldValue);
}
}
/// <summary>
/// Visit a parse tree produced by <see cref="CalculatorParser.decrementExpr"/>.
/// <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 VisitDecrementExpr([NotNull] CalculatorParser.DecrementExprContext context)
{
return(VisitChildren(context));
}
