The 'use' that perl is complaining about is '$[ = $[+1'. From perlvar,

As of release 5 of Perl, assignment to $[ is treated as a compiler directive

You can assign to it at compile time (ie $[ = 5; ), but cannot modify it at runtime (ie $[++; ).

In reply to Re: Playing with $[ by jsprat
in thread Playing with $[ by LAI

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