/// <summary>
/// Folds a named capture node.
/// </summary>
/// <param name="namedCapture"></param>
/// <param name="argument">The argument to be passed to the visitor method.</param>
/// <returns>
/// <list type="number">
/// <item>The original node if it's to be kept</item>
/// <item>A different node to replace the original node with</item>
/// <item>Null if the node is to be removed</item>
/// </list>
/// </returns>
protected override GrammarNode <Char>?VisitNamedCapture(NamedCapture namedCapture, TArgument argument)
{
if (namedCapture is null)
{
throw new ArgumentNullException(nameof(namedCapture));
}
GrammarNode <Char>?innerNode = this.Visit(namedCapture.InnerNode, argument);
if (innerNode is null)
{
return(null);
}
else if (innerNode == namedCapture.InnerNode)
{
return(namedCapture);
}
else
{
return(new NamedCapture(namedCapture.Name, innerNode));
}
}
protected override String?VisitNamedCapture(NamedCapture namedCapture, Unit argument) => this.Visit(namedCapture.InnerNode, default);
/// <summary> /// Visits a named capture. /// </summary> /// <param name="namedCapture"></param> /// <param name="argument">The argument data passed by the caller.</param> /// <returns>The result of visiting this node.</returns> protected abstract TReturn VisitNamedCapture(NamedCapture namedCapture, TArgument argument);
