From perldiag (I think this is only in 5.6, so perlmonk doesn't have it) : 
No such pseudo-hash field ""%s""
(F) You tried to access an array as a hash, but the
field name used is not defined.  The hash at index 0
should map all valid field names to array indices for
that to work.

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Without seeing how your pseudohash is created I imagine that the structure of the array behind $foo, or its hash members is not what you think, or simply doesn't contain the 'blah' key.

Additionally, perl is probably interpreting @$foo as a pseudohash is because your sort routine references them as such : 

$a->{'blah'} cmp $b->{'blah'}

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maybe 
$$a->{'blah'} cmp $$b->{'blah'}

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would work, but I'm really just guessing there, since your data structure isn't apparent.

In reply to Re: Pseudo-hash intrusion... (boo) by boo_radley
in thread Pseudo-hash intrusion... by dragonchild

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