old_contents: 'use strict';
  
  /**
   * Determine information about the failed validation
   * check.
   *
   * @param {any} value
   * @param {Object} result The error object
   * @returns {String} Human readable error message
   */
  export default function getErrorClue(value, result) {
      switch(result.type) {
          case 'wrapper.validator':
              return `Custom validator failed for value "${value}".`;
          case 'wrapper.equals':
              return `The given value "${value}" did not strictly equal "${result.info.expectedValue}".`;
          case 'nativetype':
              return `Expected${result.optional ? `optional ` : ``} ${result.info.expectedType}, got ${result.info.got}.`;
          case 'instanceof':
              return `Expected${result.optional ? `optional ` : ``} instance of ${result.info.expectedInstance}, got ${result.info.got}.`;
          case 'array-literal':
              return `Expected${result.optional ? `optional ` : ``} array, got ${result.info.got}.`;
          case 'object-literal':
              return `Expected${result.optional ? `optional ` : ``} object, got ${result.info.got}.`;
      }
  };
  
new_contents: 'use strict';
  
  /**
   * Determine information about the failed validation
   * check.
   *
   * @param {any} value
   * @param {Object} result The error object
   * @returns {String} Human readable error message
   */
  export default function getErrorClue(value, result) {
      switch(result.type) {
          case 'wrapper.validator':
              return `Custom validator failed for value "${value}".`;
          case 'wrapper.equals':
              return `The given value "${value}" did not strictly equal "${result.info.expectedValue}".`;
          case 'nativetype':
              return `Expected${result.optional ? ` optional` : ``} ${result.info.expectedType}, got ${result.info.got}.`;
          case 'instanceof':
              return `Expected${result.optional ? ` optional` : ``} instance of ${result.info.expectedInstance}, got ${result.info.got}.`;
          case 'array-literal':
              return `Expected${result.optional ? ` optional` : ``} array, got ${result.info.got}.`;
          case 'object-literal':
              return `Expected${result.optional ? ` optional` : ``} object, got ${result.info.got}.`;
      }
  };
  
subject: fix typos in error messages