stanfordnlp/CoreNLP · error · SemgrexParseException

GraphRelation had both = and ~ set, but the names were…

Error message

GraphRelation had both = and ~ set, but the names were different!

What it means

The GraphRelation constructor throws SemgrexParseException when both a node-name binding (=name) and an edge-name binding (~name) are present but differ. A GraphRelation can only carry one consistent name; conflicting names would make the pattern ambiguous.

Solutions

Use the same name for both = and ~ bindings, or drop one of them
Edit the Semgrex pattern string so the node name (=x) and edge name (~x) match
If names must differ, keep only the one you intend to bind

Example fix

// before
String pattern = "{word:dog} >=subj=nsubj~edge";
// after
String pattern = "{word:dog} >=subj=nsubj~subj";

Defensive patterns

Strategy: try-catch

Validate before calling

if (name != null && edgeName != null && !name.equals(edgeName)) throw new IllegalArgumentException("= and ~ names must match: " + name + " vs " + edgeName);

Try / catch

try { GraphRelation r = GraphRelation.createRelation(reln, type, name, edgeName); } catch (SemgrexParseException e) { log.error("Inconsistent pattern names: " + e.getMessage()); }

Prevention

Use identical names for = (node) and ~ (edge) bindings in Semgrex patterns
Validate pattern strings with the Semgrex parser before deploying them in configs
Keep name tokens generated from one variable so they cannot diverge

When it happens

Trigger: Parsing a Semgrex relation like ">=foo~bar" where the = name and the ~ edgeName are both set to different strings, via GraphRelation.createRelation or the Semgrex parser.

Common situations: Typo in a hand-written Semgrex pattern assigning different names to the node and the edge; generated patterns concatenating name fragments incorrectly.

Related errors

AI-assisted analysis of stanfordnlp/CoreNLP@1b7edd19c4 (2026-09-10). Data as JSON: /api/errors/d8c3ddda40dccd48. Report an issue: GitHub.

Appendix: source

Thrown at src/edu/stanford/nlp/semgraph/semgrex/GraphRelation.java:63

  /**
   * Returns <code>true</code> iff this <code>GraphRelation</code> holds between
   * the given pair of nodes in the given semantic graph.
   */
  abstract boolean satisfies(IndexedWord n1, IndexedWord n2, SemanticGraph sg);

  /**
   * For a given node and its root, returns an {@link Iterator} over the nodes
   * of the semantic graph that satisfy the relation.
   */
  abstract Iterator<IndexedWord> searchNodeIterator(IndexedWord node, SemanticGraph sg);

  private GraphRelation(String symbol, String type, String name, String edgeName) {
    this.symbol = symbol;
    this.type   = getPattern(type);
    this.rawType = type;
    this.edgeName = edgeName;
    if (name != null && edgeName != null && !name.equals(edgeName)) {
      throw new SemgrexParseException("GraphRelation had both = and ~ set, but the names were different!  " + this.toString());
    }
    if (name != null) {
      this.name = name;
    } else {
      this.name = edgeName;
    }
  }

  private GraphRelation(String symbol, String type, String name) {
    this(symbol, type, name, null);
  }

  private GraphRelation(String symbol, String type) {
    this(symbol, type, null);
  }

  private GraphRelation(String symbol) {
    this(symbol, null);

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