> how could I recognize if current element is a scalar or another list to recurse?

with ref

> What is missing in this structure is theplaceholder, which will have a group name... 

No idea what you may mean...

update

Maybe

 [ {A => [1, {B => [2,3,4]} ,5, {C => [ 6, { D => [7,8,9] } ] } ]

? ? ?

(untested)

update

TIMTOWTDI

Instead of a one element hash you could use a 2 element array.

Or put the "placeholder" into the sub array as first element.

I personally prefer the hash solution for readability, but keep in mind that keys are stringified.

Cheers Rolf

(addicted to the Perl Programming Language and ☆☆☆☆ :)

In reply to Re^3: How might I handle a special tree? (updated) by LanX
in thread How might I handle a special tree? by vitoco

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