code: function readYamlSync(filePath, opts_) {
    var parserOptions;
    if (typeof opts_ !== 'undefined') {
      parserOptions = typeof opts_ === 'function' ? { map: opts_ } : opts_;
    }
    return readDataSync(filePath, { parser: parserYaml, parserOptions: parserOptions });
  }
docs: Synchronously read a yaml file. Returns an empty object if file is empty. `parseOptions` will pass any other optinos directl to js-yaml library. See its documentation for more detail https://github.com/nodeca/js-yaml
  
  @function readYamlSync
  @param {String} filePath Input file path
  @param {Function|Object} [parserOptions] Optional map function or an object specifying the optional options below.
  @param {Function} [parserOptions.map] Optional map function. Called once for each row (header row skipped). If your file is an array (it tests if first non-whitespace character is a `[`), the callback has the signature `(row, i)` and delegates to `_.map`. Otherwise it's considered an object and the callback has the signature `(value, key)` and delegates to `_.mapObject`. See example below.
  @param {String} [parserOptions.loadMethod="safeLoad"] The js-yaml library allows you to specify a more liberal `"load"` method which will accept RegExp and function values in your file.
  @returns {Array|Object} the contents of the file as a string
  
  @example
  // Can be `.yaml` or `.yml` extension
  var data = io.readYamlSync('path/to/data.yaml')
  console.log(data) // json data
  
  // With map function
  var data = io.readYaml('path/to/data.yaml', function (yamlFile) {
  yamlFile.height = yamlFile.height * 2
  return yamlFile
  })
  console.log(data) // json data with `height` values doubled
  
  // With map function and load settings
  var data = io.readYaml('path/to/data.yaml', {
  loadMethod: 'load',
  map: function (yamlFile) {
  yamlFile.height = yamlFile.height * 2
  return yamlFile
  }
  })
  console.log(data) // json data with `height` values doubled