It's not NP-Complete, I promise.

Create a function that when given a list, returns a hash-ref based on that list's specification. A quick example: 
my $h = f(qw[ foo => zoo moo too
              bar => car far
              bar => zar tar
              qux => mux ]);

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In this case, $h should be defined as: 
$h = { foo => [ 'zoo','moo','too','bar' ],
       bar => [ 'car','far','zar','tar' ],
       qux => [ 'mux' ] };

[download]
Note that the input can be anything at all, provided it is in list format, and the keys are valid keys, and that further the symbol '=>' is reserved as an identifier. There may be key conflicts with the key, in which case the new data is appended to the existing data, as shown in the example with 'bar'.

In reply to (Golf) List to Hash by tadman

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