Then just use one hash, since you never use the same value as both a key and a value... 

    my %chordpos;
    @chordpos{1..12}= qw( A A# ... );
    @chordpos{values %chordpos}= keys %chordpos;

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                - tye

In reply to Re: Bijective data association structure? (1 hash) by tye
in thread Bijective data association structure? by FoxtrotUniform

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