@Override
	public String toString() {
		if (label != null) {
			return label + ":" + tag;
		}

		return tag;
	}
This method returns a text representation of the tag chunk. Labeled tags
are returned in the form {@code label:tag}, and unlabeled tags are
returned as just the tag name.
runtime/Java/src/org/antlr/v4/runtime/tree/pattern/TagChunk.java