Word description Deserializes the YAML formatted string into a Factor object. Throws yaml-no-document when there is no document (for example the empty string).
Notes Contrary to yaml-docs>, this word only parses the input until one document is produced. Valid or invalid content after the first document is ignored. To verifiy that the whole input is one valid YAML document, use yaml-docs> and assert that the length of the output array is 1.