code: function assertSingleOwner(replicant, value) {
  	let metadata;
  	if (proxySet.has(value)) {
  		metadata = proxyMetadataMap.get(value);
  	} else if (metadataMap.has(value)) {
  		metadata = metadataMap.get(value);
  	} else {
  		// If there's no metadata for this value, then it doesn't belong to any Replicants yet,
  		// and we're okay to continue.
  		return;
  	}
  
  	if (metadata.replicant !== replicant) {
  		/* eslint-disable function-paren-newline */
  		throw new Error(
  			`This object belongs to another Replicant, ${metadata.replicant.namespace}::${metadata.replicant.name}.` +
  			`\nA given object cannot belong to multiple Replicants. Object value:\n${JSON.stringify(value, null, 2)}`
  		);
  		/* eslint-enable function-paren-newline */
  	}
  }
docs: Throws an exception if an object belongs to more than one Replicant.
  @param replicant {object} - The Replicant that this value should belong to.
  @param value {*} - The value to check ownership of.