import * as mod from "https://dotland.deno.dev/std@0.57.0/bytes/mod.ts"; FunctionsfconcatConcatenate two binary arrays and return new one. fcontainsCheck srouce array contains pattern array. fequalCheck whether binary arrays are equal to each other. ffindIndexFind first index of binary pattern from a. If not found, then return -1 ffindLastIndexFind last index of binary pattern from a. If not found, then return -1. fhasPrefixCheck whether binary array starts with prefix. fhasSuffixCheck whether binary array ends with suffix. frepeatRepeat bytes. returns a new byte slice consisting of count copies of b.