Missing API in PARI?

[Ilya Zakharevich <ilya@math.ohio-state.edu>]

>From the calculator you can set

     a[2] = 7
     aa[2,] = [4,5,6]
     aa[,3] = [7,8]~
     aa[2,3] = 4

Is it possible to do it from PARI?  I could not find it in 1.39, did
it change in 2.0?  Currently you cannot make an operation like the
above one in Perl - when using Math::Pari...

Note that in the above examples the calculator makes some assumptions
about layout of a and aa in memory (these assumptions are valid for
data created by calculator), so it may be that in order to create such
an API one may need to introduce an additional flag and mark GENs
which are created in consequent chunks as such...

Ilya