stanfordnlp/CoreNLP · error · IllegalArgumentException

Not a valid dashes style

Error message

Not a valid dashes style: ${value}

What it means

SpanishLexer's constructor accepts a 'dashes' option controlling how dash characters are tokenized, mapped to LexerUtils.DashesEnum via Enum.valueOf. Any value that is not a valid DashesEnum constant (after trim/uppercase) causes this IllegalArgumentException naming the offending value.

Solutions

1. Set a valid DashesEnum value such as 'dashes=unicode', 'dashes=delete', or 'dashes=leave' (match LexerUtils.DashesEnum for your version).
2. Inspect LexerUtils.DashesEnum to confirm accepted constants in the version in use.
3. Pre-validate the value in config loading code and reject bad tokens early.
4. Catch IllegalArgumentException around lexer construction and log the offending key/value.

Example fix

// before
new SpanishLexer(reader, "dashes=em-dash");
// after
new SpanishLexer(reader, "dashes=unicode");

String v = value.trim().toUpperCase(Locale.ROOT);
boolean ok = java.util.Arrays.stream(LexerUtils.DashesEnum.values())
    .anyMatch(e -> e.name().equals(v));
if (!ok) throw new IllegalArgumentException("Bad dashes option: " + value);

static boolean isValidDashesStyle(String value) {
  if (value == null) return false;
  String v = value.trim().toUpperCase(Locale.ROOT);
  for (LexerUtils.DashesEnum e : LexerUtils.DashesEnum.values())
    if (e.name().equals(v)) return true;
  return false;
}

try {
  lexer = new SpanishLexer(reader, options);
} catch (IllegalArgumentException e) {
  if (e.getMessage().contains("Not a valid dashes style")) {
    lexer = new SpanishLexer(reader, options.replaceAll("dashes=[^,]*", "dashes=unicode"));
  } else { throw e; }
}

When it happens

Trigger: Constructing SpanishLexer with options 'dashes=<value>' where value is not a DashesEnum name (e.g. 'hyphen', 'em-dash', '', or an alias removed in the current version).

Common situations: Reusing PTBTokenizer 'dashes' settings that differ; hand-edited tokenizer properties files; migrating between CoreNLP versions where enum constant names changed; whitespace/encoding artifacts in the value string (leading/trailing chars are trimmed, but inner junk is not).

Understand the failure class

Background: Invalid enum value errors: "Unknown type", "Invalid scope", "must be one of" — when a string is not on the library's allowed list — this error's family across 23 libraries.

Related errors

• Not a valid ellipses style
• SpanishLexer: Invalid option value in constructor
• Not a valid ellipses style:
• TokenizerAnnotator: unknown tokenize.class property
• TokenizerAnnotator: unknown tokenize.language property

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/0253bdf41b8c384b. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/international/spanish/process/SpanishLexer.java:14158

          } else if ("normalizeAmpersandEntity".equals(key)) {
            normalizeAmpersandEntity = val;
          } else if ("normalizeFractions".equals(key)) {
            normalizeFractions = val;
          } else if ("normalizeParentheses".equals(key)) {
            normalizeParentheses = val;
          } else if ("normalizeOtherBrackets".equals(key)) {
            normalizeOtherBrackets = val;
          } else if ("ellipses".equals(key)) {
            try {
              ellipsisStyle = LexerUtils.EllipsesEnum.valueOf(value.trim().toUpperCase(Locale.ROOT));
            } catch (IllegalArgumentException iae) {
              throw new IllegalArgumentException ("Not a valid ellipses style: " + value);
            }
          } else if ("dashes".equals(key)) {
            try {
              dashesStyle = LexerUtils.DashesEnum.valueOf(value.trim().toUpperCase(Locale.ROOT));
            } catch (IllegalArgumentException iae) {
              throw new IllegalArgumentException ("Not a valid dashes style: " + value);
            }
          } else if ("escapeForwardSlashAsterisk".equals(key)) {
            escapeForwardSlashAsterisk = val;
          } else if ("untokenizable".equals(key)) {
            switch (value) {
              case "noneDelete":
                untokenizable = UntokenizableOptions.NONE_DELETE;
                break;
              case "firstDelete":
                untokenizable = UntokenizableOptions.FIRST_DELETE;
                break;
              case "allDelete":
                untokenizable = UntokenizableOptions.ALL_DELETE;
                break;
              case "noneKeep":
                untokenizable = UntokenizableOptions.NONE_KEEP;
                break;
              case "firstKeep":

View on GitHub (pinned to 1b7edd19c4)