#!/bin/bash
echo "[as1,as2,as3],[as4,as5]" | perl -lpe 's/(?:\[|\G(?!^))[^]]*?\K,/|/g'
echo "[as1,as2,as3],[as4,as5]" | perl -lpe 's/(?:\[|\G(?!^))[^],]*\K,/|/g'
IyEvYmluL2Jhc2gKZWNobyAiW2FzMSxhczIsYXMzXSxbYXM0LGFzNV0iIHwgcGVybCAtbHBlICdzLyg/OlxbfFxHKD8hXikpW15dXSo/XEssL3wvZycKZWNobyAiW2FzMSxhczIsYXMzXSxbYXM0LGFzNV0iIHwgcGVybCAtbHBlICdzLyg/OlxbfFxHKD8hXikpW15dLF0qXEssL3wvZycK