cross origin strings

一、获取跨域字符串

export function getCrossOriginString(
  input?: string,
): CrossOriginString | undefined {
  if (typeof input === 'string') {
    return input === 'use-credentials' ? input : '';
  }
  return undefined;
}

二、获取跨域字符串为

export function getCrossOriginStringAs(
  as?: string,
  input?: string,
): undefined | CrossOriginString {
  if (as === 'font') {
    return '';
  }
  if (typeof input === 'string') {
    return input === 'use-credentials' ? input : '';
  }
  return undefined;
}

三、导出类型

export opaque type CrossOriginString = string;