/// <summary>
/// Creates a transducer that replaces escaped argument placeholders with the corresponding arguments.
/// </summary>
/// <param name="escapedArgs">The list of arguments.</param>
/// <param name="transpose">Specifies whether the created transducer should be transposed (useful for backward message computation).</param>
/// <returns>The created transducer.</returns>
private static StringTransducer GetPlaceholderReplacingTransducer(IList <StringAutomaton> escapedArgs, bool transpose)
{
var alternatives = new List <StringTransducer>();
for (int i = 0; i < escapedArgs.Count; ++i)
{
StringTransducer alternative = StringTransducer.ConsumeElement((char)('0' + i));
alternative.AppendInPlace(StringTransducer.Produce(escapedArgs[i]), (byte)(i + 1));
alternatives.Add(alternative);
}
StringTransducer result = DisallowBraceReplacersTransducer.Clone();
result.AppendInPlace(StringTransducer.ConsumeElement(LeftBraceReplacer));
result.AppendInPlace(StringTransducer.Sum(alternatives));
result.AppendInPlace(StringTransducer.ConsumeElement(RightBraceReplacer));
result = StringTransducer.Repeat(result, minTimes: 0);
result.AppendInPlace(DisallowBraceReplacersTransducer);
if (transpose)
{
result.TransposeInPlace();
}
return(result);
}
public void Sum()
{
StringTransducer replace = StringTransducer.Sum(
StringTransducer.Replace(DiscreteChar.Lower(), DiscreteChar.Digit()),
StringTransducer.Replace(DiscreteChar.Lower(), DiscreteChar.LetterOrDigit()));
StringInferenceTestUtilities.TestTransducerValue(replace, "hello", "123", 2.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "w", "1337", 2.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "w", string.Empty, 2.0);
StringInferenceTestUtilities.TestTransducerValue(replace, string.Empty, "17", 2.0);
StringInferenceTestUtilities.TestTransducerValue(replace, string.Empty, string.Empty, 2.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "hello", "worlds", 1.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "hello", "WORLDS111", 1.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "123", "worlds", 0.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "123", "123", 0.0);
StringInferenceTestUtilities.TestTransducerValue(replace, "1", string.Empty, 0.0);
}
/// <summary>
/// Creates a transducer that replaces argument placeholders with the corresponding arguments.
/// </summary>
/// <param name="args">The list of arguments.</param>
/// <param name="argNames">The list of argument names.</param>
/// <param name="forBackwardMessage">Specifies whether the created transducer should be transposed so that the backward message can be computed.</param>
/// <param name="withGroups">Specifies whether filled in arguments should be labeled with different groups.</param>
/// <returns>The created transducer.</returns>
private static StringTransducer GetPlaceholderReplacingTransducer(
IList <StringAutomaton> args, IReadOnlyList <string> argNames, bool forBackwardMessage, bool withGroups)
{
var alternatives = new List <StringTransducer>();
for (int argumentIndex = 0; argumentIndex < args.Count; ++argumentIndex)
{
StringTransducer alternative;
if (!forBackwardMessage)
{
alternative = StringTransducer.Consume(argNames[argumentIndex]);
alternative.AppendInPlace(StringTransducer.Produce(args[argumentIndex]), withGroups ? argumentIndex + 1 : 0);
}
else
{
// After transposing 'Produce' will become 'Consume',
// and starting from 'Consume' makes projection computations more efficeint because it allows to detect dead braches earlier
Debug.Assert(!withGroups, "Groups are never needed for backward message.");
alternative = StringTransducer.Produce(args[argumentIndex]);
alternative.AppendInPlace(StringTransducer.Consume(argNames[argumentIndex]));
}
alternatives.Add(alternative);
}
StringTransducer result = DisallowBracesTransducer.Clone();
result.AppendInPlace(StringTransducer.ConsumeElement('{'));
result.AppendInPlace(StringTransducer.Sum(alternatives));
result.AppendInPlace(StringTransducer.ConsumeElement('}'));
result = StringTransducer.Repeat(result, minTimes: 0);
result.AppendInPlace(DisallowBracesTransducer);
if (forBackwardMessage)
{
result = StringTransducer.Transpose(result);
}
return(result);
}
