function fastConcatMUimport { fastConcatMU } from "https://deno.land/x/steam_trader@v0.4.0/src/utils.ts"; fastConcatMU<T>(a: Array<T>, b: Array<T>): voidmutates original array (first arg), runs no checks Type ParametersTParametersa: Array<T>b: Array<T>Returnsvoid