/// <summary>
/// Attempts to get a token of the given type.
/// </summary>
/// <returns>The result of the search.</returns>
public TokenResult GetToken()
{
TokenResult result = tokenSource.GetToken();
if (result != null)
{
tokens.Add(result);
}
return(result);
}
protected override TokenResult GetNextToken()
{
if (index >= tokens.Count)
{
return(null);
}
TokenResult result = tokens[index];
++index;
return(result);
}
/// <summary>
/// Attempts to match the expression item with the values returned by the parser.
/// </summary>
/// <param name="attempt">The parser currently iterating over the token source.</param>
/// <param name="itemName">The name of the token in the outer expression.</param>
/// <returns>The results of the match.</returns>
public MatchResult Match(IParseAttempt attempt, string itemName)
{
TokenResult tokenResult = attempt.GetToken();
bool isMatch = tokenResult != null && tokenResult.Name == TokenType;
MatchResult result = new MatchResult()
{
ItemName = itemName,
IsMatch = isMatch,
Context = tokenResult,
};
return(result);
}
protected override TokenResult GetNextToken()
{
if (index >= commandText.Length)
{
return(null);
}
TokenResult result = registry.ExtractToken(commandText, ref index);
if (result == null && !String.IsNullOrWhiteSpace(commandText.Substring(index)))
{
throw new SQLGenerationException("Encountered an unknown token type.");
}
return(result);
}
/// <summary>
/// Restores the given token to the front of the token stream.
/// </summary>
/// <param name="result">The token to restore.</param>
public void PutBack(TokenResult result)
{
undo.Push(result);
}
/// <summary>
/// Adds a token to the stream.
/// </summary>
/// <param name="result">The token result to add.</param>
/// <returns>The current token stream.</returns>
public TokenStream Add(TokenResult result)
{
tokens.Add(result);
return this;
}
/// <summary>
/// Adds a token to the stream.
/// </summary>
/// <param name="result">The token result to add.</param>
/// <returns>The current token stream.</returns>
public TokenStream Add(TokenResult result)
{
tokens.Add(result);
return(this);
}
/// <summary>
/// Restores the given token to the front of the token stream.
/// </summary>
/// <param name="result">The token to restore.</param>
public void PutBack(TokenResult result)
{
undo.Push(result);
}