Question about ArrayArray#

Michal Terepeta michal.terepeta at
Wed May 2 11:30:29 UTC 2018

Hi all,

I have a quick question about ArrayArray#. Is it safe to store *both* an
ByteArray# and ArrayArray# within the *same* ArrayArray#? For instance:
- at index 0 of an ArrayArray# I store a different ArrayArray#,
- at index 1 of that same ArrayArray# I store a ByteArray#.

It seems to me that this should be safe/supported from the point of view of
the runtime system:
- both ArrayArray# and ByteArray# have the same kind/runtime representation,
- the arrays have a header that tells rts/GC what they are/how to handle
(But I, as a user, would be responsible for using the right primop with the
right index to read them back)

Is this correct?

Thanks a lot!

- Michal

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