#!/usr/bin/perl -p
#12345678 1 2345678 2 2345678 3 2345678 4 2345678 5 2345678
 s#\B(\w+)\B#join$,,(split$,,$1)[sub{my($l,@x)=@_;$l=$x[$l]
 =pop while@_;@x}->(sort{(-1,1)[rand 2]}0..-1+length$1)]#ge
# 6 12345678 7 2345678 8 2345678 9 2345678 0 2345678 1 2345

##</code><code>##

#!/usr/bin/perl -p
#12345678 1 2345678 2 2345678 3 2345678 4 2345678 5 2345
 s#\B\w+\B#join$,,(split$,,$&)[sub{($b,@*)=@_;$b=$*[$b]=
 pop while@_;@*}->(sort{(-1,1)[rand 2]}0..length$&)]#ge
#678 6 12345678 7 2345678 8 2345678 9 2345678 0 2345678

##</code><code>##

     sort {(-1,1)[rand 2]} ...

##</code><code>##

    sort {-.5+rand} ...

##</code><code>##

#!/usr/bin/perl -p
#12345678 1 2345678 2 2345678 3 2345678 4 2345678 5 23
 s#\B\w+\B#join$,,(split$,,$&)[sub{($b,@*)=@_;$b=$*[$b
 ]=pop while@_;@*}->(sort{rand~0}0..-1+length$&)]#ge
#45678 6 12345678 7 2345678 8 2345678 9 2345678 0 23