rc/sh/similar

#!/usr/bin/env sh
# YES_ZSH

similar() {
    awk '
    {
        i=0
        split($0,a,"")
        split(L,b,"")
        for (c in a)
            if (a[c]==b[c]) i++
            else break
        #print substr($0,1,i) "\033[7m" substr($0,i+1) "\033[0m"
        print "\033[31m" substr($0,1,i) "\033[0m" substr($0,i+1)
        L=$0
    }'
}

[ "${SOURCING:-0}" -gt 0 ] || similar "$@"