use perlfunc:ref to see if the value of $somehash{"$foo$bar"} is an arrayref. If it isn't, then create it. 

unless ( ref ($somehash{"$foo$bar"} eq 'ARRAY' ) {
    $somehash{"$foo$bar"} = [];
}
...

[download]

HTH

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

In reply to Re: push onto hash! by arturo
in thread push onto hash! by Anonymous Monk

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