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petitparser/lib/src/core/token.dart

-part of petitparser;
-
-/**
- * A token represents a parsed part of the input stream.
- *
- * The token holds the resulting value of the input, the input buffer,
- * and the start and stop position in the input buffer. It provides many
- * convenience methods to access the state of the token.
- */
-class Token {
-
-  /**
-   * The parsed value of the token.
-   */
-  final value;
-
-  /**
-   * The parsed buffer of the token.
-   */
-  final buffer;
-
-  /**
-   * The start position of the token in the buffer.
-   */
-  final int start;
-
-  /**
-   * The stop position of the token in the buffer.
-   */
-  final int stop;
-
-  /**
-   * Constructs a token from the parsed value, the input buffer, and the
-   * start and stop position in the input buffer.
-   */
-  const Token(this.value, this.buffer, this.start, this.stop);
-
-  /**
-   * The consumed input of the token.
-   */
-  get input => buffer is String
-      ? buffer.substring(start, stop)
-      : buffer.sublist(start, stop);
-
-  /**
-   * The length of the token.
-   */
-  int get length => stop - start;
-
-  /**
-   * The line number of the token (only works for [String] buffers).
-   */
-  int get line => Token.lineAndColumnOf(buffer, start)[0];
-
-  /**
-   * The column number of this token (only works for [String] buffers).
-   */
-  int get column => Token.lineAndColumnOf(buffer, start)[1];
-
-  @override
-  String toString() => 'Token[${positionString(buffer, start)}]: $value';
-
-  @override
-  bool operator ==(other) {
-    return other is Token
-        && value == other.value
-        && start == other.start
-        && stop == other.stop;
-  }
-
-  @override
-  int get hashCode => value.hashCode + start.hashCode + stop.hashCode;
-
-  static final Parser _NEWLINE_PARSER =
-      char('\n').or(char('\r').seq(char('\n').optional()));
-
-  /**
-   * Returns a parser for that detects newlines platform independently.
-   */
-  static Parser newlineParser() => _NEWLINE_PARSER;
-
-  /**
-   * Converts the [position] index in a [buffer] to a line and column tuple.
-   */
-  static List<int> lineAndColumnOf(String buffer, int position) {
-    var line = 1, offset = 0;
-    for (var token in newlineParser().token().matchesSkipping(buffer)) {
-      if (position < token.stop) {
-        return [line, position - offset + 1];
-      }
-      line++;
-      offset = token.stop;
-    }
-    return [line, position - offset + 1];
-  }
-
-  /**
-   * Returns a human readable string representing the [position] index in a [buffer].
-   */
-  static String positionString(buffer, int position) {
-    if (buffer is String) {
-      var lineAndColumn = Token.lineAndColumnOf(buffer, position);
-      return '${lineAndColumn[0]}:${lineAndColumn[1]}';
-    } else {
-      return '${position}';
-    }
-  }
-}