Hi,

I tried to reproduce exactly your scenario, but I do not get any weird result:

  DB<1>  @L = 0..27; # use @L rather than @l for more clarity (avoid m
+istaking 1 and l)

  DB<2>  p $#L;
27
  DB<3> @F = 0..23;

  DB<4> p $#F;
23
  DB<5>  use List::Util 'max';

  DB<6> p max($#L, $#F);
27
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Perhaps you should show how @l and @F are populating, although I fail to see what it could be at this point.

My Perl version:

perl 5, version 14, subversion 4 (v5.14.4)
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