/// <inheritdoc />
public IEnumerable <char> Process(char input)
{
if (this.inputPreprocessors.Count == 0)
{
yield return(input);
yield break;
}
Queue <PreprocessedInput> processQueue = queuePool.Create();
Queue <PreprocessedInput> outputQueue = queuePool.Create();
processQueue.Enqueue(input);
foreach (var preprocessor in this.inputPreprocessors)
{
while (processQueue.Count > 0)
{
var toProcess = processQueue.Dequeue();
if (toProcess.Replacement != null)
{
foreach (var toProcessChar in toProcess.Replacement)
{
outputQueue.Enqueue(preprocessor.Preprocess(toProcessChar));
}
}
else
{
outputQueue.Enqueue(preprocessor.Preprocess(toProcess.Value));
}
}
outputQueue = Interlocked.Exchange(ref processQueue, outputQueue);
}
while (processQueue.Count > 0)
{
var toReturn = processQueue.Dequeue();
if (toReturn.Replacement != null)
{
foreach (var letter in toReturn.Replacement)
{
yield return(letter);
}
}
else
{
yield return(toReturn.Value);
}
}
queuePool.Return(processQueue);
queuePool.Return(outputQueue);
}
