text: export function handleError(...arg) {
    console.error('[rc-image-loader]', ...arg) // eslint-disable-line no-console
  }
  
  export function handleWarning(...arg) {
    console.warn('[rc-image-loader]', ...arg) // eslint-disable-line no-console
  }
  
  export function isFunction(fn: any): boolean {
    return fn && typeof fn === 'function'
  }
  
  export function isString(str: any): boolean {
    return str && typeof str === 'string'
  }
  