The parameter passed to the second call to "increment" is the AOA consisting of the tuples resulting from the first call.

Since your code that creates @a basically references elements of existing tuples (which now are references), perl does not create NEW references .. it uses existing addresses of these items.

This is what Dumper tries to show you - some elements reference things inside yourself!

The actual values generated are indeed proper tuples the way you expect .. they just happen to be references to existing stuff.

FYI - the "increment" sub could be condensed to a single statement: 

   return [ map {[$d->[$_-1],$d->[$_]]} 1..$#$d ];

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                Memory fault   --   brain fried

In reply to Re: Array of Arrays: why is "$VAR1->[0][1]" and the like embedded within? by NetWallah
in thread Array of Arrays: why is "$VAR1->[0][1]" and the like embedded within? by corenth

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