/// <summary>
/// Initializes a new instance of the <see cref="ParseErrorException" /> class.
/// </summary>
/// <param name="error">The error message.</param>
/// <param name="expression">The expression.</param>
/// <param name="location">The error location.</param>
/// <param name="innerException">The inner exception.</param>
public ParseErrorException(string error, string expression, Location location, Exception innerException)
: base(location.BuildParseError(error, expression), innerException)
{
Error = error;
Expression = expression;
Location = location.Clone();
}
/// <summary>
/// Initializes a new instance of the <see cref="ParseErrorException" /> class.
/// </summary>
/// <param name="error">The error message.</param>
/// <param name="expression">The expression.</param>
/// <param name="location">The error location.</param>
/// <param name="innerException">The inner exception.</param>
public ParseErrorException(string error, string expression, Location location, Exception innerException)
: base(location.BuildParseError(error, expression), innerException)
{
Error = error;
Expression = expression;
Location = location.Clone();
}
private bool Next()
{
int line, column;
RemainingExpression = RemainingExpression.TrimStart(out line, out column);
Location.Line += line;
Location.Column = line > 0 ? column : Location.Column + column;
if (RemainingExpression.Length == 0)
{
return(false);
}
foreach (var kvp in RegexMap)
{
var regex = kvp.Value;
var match = regex.Match(RemainingExpression);
if (!match.Success)
{
continue;
}
var value = match.Value;
Token = new Token(kvp.Key, ConvertTokenValue(kvp.Key, value), Location.Clone());
RemainingExpression = RemainingExpression.Substring(value.Length, out line, out column);
Location.Line += line;
Location.Column = line > 0 ? column : Location.Column + column;
return(true);
}
throw new ParseErrorException("Invalid token.", Expr, Location);
}
/// <summary>
/// Analyzes a specified logical expression and extracts a sequence of tokens.
/// </summary>
/// <param name="expression">The logical expression.</param>
/// <returns>
/// A sequence of extracted tokens.
/// </returns>
/// <exception cref="System.ArgumentNullException">expression;Expression not provided.</exception>
/// <exception cref="ParseErrorException"></exception>
public IEnumerable <Token> Analyze(string expression)
{
if (expression == null)
{
throw new ArgumentNullException(nameof(expression), "Expression not provided.");
}
lock (_locker)
{
Location = new Location(1, 1);
Expr = RemainingExpression = expression;
var tokens = new List <Token>();
while (Next())
{
tokens.Add(Token);
}
// once we've reached the end of the string, EOF token is returned - thus, parser's lookahead does not have to worry about running out of tokens
tokens.Add(new Token(TokenType.EOF, string.Empty, Location.Clone()));
return(tokens);
}
}
/// <summary>
/// Analyzes a specified logical expression and extracts a sequence of tokens.
/// </summary>
/// <param name="expression">The logical expression.</param>
/// <returns>
/// A sequence of extracted tokens.
/// </returns>
/// <exception cref="System.ArgumentNullException"><c>expression</c> is null</exception>
/// <exception cref="ParseErrorException"></exception>
public IEnumerable<Token> Analyze(string expression)
{
if (expression == null)
throw new ArgumentNullException(nameof(expression), "Expression not provided.");
lock (_locker)
{
Location = new Location(1, 1);
ExprString = RemainingExprString = expression;
var tokens = new List<Token>();
while (Next())
{
tokens.Add(Token);
}
// once we've reached the end of the string, EOF token is returned - thus, parser's lookahead does not have to worry about running out of tokens
tokens.Add(new Token(TokenType.EOF, string.Empty, string.Empty, Location.Clone()));
return tokens;
}
}
