import { Item, InnerList } from './types';

const asciiRe = /^[\x20-\x7E]*$/;
const tokenRe = /^[a-zA-Z*][:/!#$%&'*+\-.^_`|~A-Za-z0-9]*$/;
const keyRe = /^[a-z*][*\-_.a-z0-9]*$/;

export function isAscii(str: string): boolean {

  return asciiRe.test(str);

}

export function isValidTokenStr(str: string): boolean {

  return tokenRe.test(str);

}

export function isValidKeyStr(str: string): boolean {

  return keyRe.test(str);

}


export function isInnerList(input: Item | InnerList): input is InnerList {

  return Array.isArray(input[0]);

}