In 5.8.8, it behaves as documented. Quote 5.8.8's perlvar:

As of release 5 of Perl, assignment to $[ is treated as a compiler directive [...]. (That's why you can only assign compile-time constants to it.)

In fact, 5.10.0's perlvar still includes that line, so you've uncovered a bug. (Documentation or code bug, I don't know.)

In reply to Re: fun with $[ by ikegami
in thread fun with $[ by rolfy

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