how can I push onto an anonymous array which is a value in a hash without creating it first?

e.g. 

for (@somelist) {
    my($foo,$bar) = split;
    my $x = somecalc($foo,$bar);
    
    # this line won't work!!
    push @$somehash{$foo.$bar}, $x;
}

[download]
problem is I don't know what $foo and $bar are so I can't create the anonymous list before I get into the loop and if I did $somehash{$foo.$bar} = []; first then surely it would reset the list each time round the loop!?

please help.

In reply to push onto hash! by Anonymous Monk

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