stanfordnlp/CoreNLP · error · SsurgeonParseException

Could not find match name for " + elt

Error message

Could not find match name for " + elt

What it means

While parsing the <wordlist> test element in ssurgeon XML, the parser reads the match name from the element's text content. Because getEltText returns empty string rather than null for empty elements, the null check is a defensive guard; a truly missing/empty match name produces this SsurgeonParseException indicating the WordlistTest has no node name to match.

Solutions

  1. Add the match name as the text content of the wordlist element
  2. Ensure the name matches a node captured by the pattern's semgrex query
  3. Read the chained cause to identify the offending element in the XML

Example fix

// before (empty wordlist element)
<wordlist id="wl1" type="..." resourceID="..." />
// after
<wordlist id="wl1" type="..." resourceID="...">verb</wordlist>
Defensive patterns

Strategy: validation

Validate before calling

// ensure every wordlist element has text content before parsing
org.w3c.dom.NodeList wls = doc.getElementsByTagName("wordlist");
for (int i = 0; i < wls.getLength(); i++) {
  String text = wls.item(i).getTextContent();
  if (text == null || text.trim().isEmpty())
    throw new IllegalStateException("wordlist missing match name");
}

Try / catch

try {
  List<SsurgeonPattern> pats = ssurgeon.readFromDocument(doc);
} catch (SsurgeonParseException e) {
  log.severe("WordlistTest parse failed: " + e.getCause());
}

Prevention

When it happens

Trigger: An ssurgeon XML <wordlist> element with no text content (empty body) so no node name is available for the WordlistTest.

Common situations: Hand-edited or generated ssurgeon XML where the inner text (the semgrex node name) was deleted or the element was written self-closing.

Understand the failure class

Background: "missing required argument" and "the following required arguments were not provided": what required-argument errors mean and how to fix them — this error's family across 20 libraries.

Related errors

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/df3fa41ebdc2244b. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/semgraph/semgrex/ssurgeon/Ssurgeon.java:946

          return andPred;
        }
        break;
      case SsurgeonPattern.PREDICATE_OR_TAG:
        SsurgOrPred orPred = new SsurgOrPred();
        for (Element childElt : getChildElements(elt)) {
          SsurgPred childPred = assemblePredFromXML(childElt);
          orPred.add(childPred);
          return orPred;
        }
        break;
      case SsurgeonPattern.PRED_WORDLIST_TEST_TAG:
        String id = elt.getAttribute(SsurgeonPattern.PRED_ID_ATTR);
        String resourceID = elt.getAttribute("resourceID");
        String typeStr = elt.getAttribute("type");
        String matchName = getEltText(elt).trim(); // node name to match on

        if (matchName == null) {
          throw new SsurgeonParseException("Could not find match name for " + elt);
        }
        if (id == null) {
          throw new SsurgeonParseException("No ID attribute for element = " + elt);
        }
        return new WordlistTest(id, resourceID, typeStr, matchName);
    }

    // Not a valid node, error out!
    throw new SsurgeonParseException("Invalid node encountered during Ssurgeon predicate processing, node name="+eltName);
  }



  /**
   * Reads in the test file and prints readable to string (for debugging).
   * Input file consists of semantic graphs, in compact form.
   */
  public void testRead(File tgtDirPath) throws Exception {

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