Installing Perl6 and Panda on Ubuntu 15.10. Problems with bootstrap.pl - raku

Question

I am trying to install Panda on Ubuntu 15.10. First I tried:
git clone --recursive git://github.com/tadzik/panda.git
cd panda
perl6 bootstrap.pl
The last command gives error message:
===SORRY!=== Error while compiling bootstrap.pl
Confused
at bootstrap.pl:3
------> use v6.⏏c;
expecting any of:
statement list
Based on comments from #gfldex (see below), I then ran:
> perl6 --version
This is perl6 version 2014.07 built on parrot 6.6.0 revision 0
So the problem seems that an old version of Perl6 comes with Ubuntu 15.10.
(I installed Perl6 on Ubuntu using sudo apt-get install rakudo.)
I now tried to update my Perl6 to latest version:
wget http://rakudo.org/downloads/star/rakudo-star-2016.01.tar.gz
tar xzf rakudo-star-2016.01.tar.gz
cd rakudo-star-2016.01
perl Configure.pl --backend=moar --gen-moar
make
make install
But the last command fails with:
cd modules/panda && /home/hakon/install_rakudo/rakudo-star-2016.01/install/bin/perl6-m bootstrap.pl
==> Bootstrapping Panda
==> Installing panda from a local directory '/home/hakon/install_rakudo/rakudo-star-2016.01/modules/panda'
==> panda depends on File::Find, Shell::Command, JSON::Fast
==> Shell::Command depends on File::Find
==> Fetching File::Find
==> Building File::Find
==> Testing File::Find
Perl v6.0.0 required--this is only v5.20.2, stopped at lib/File/Find.pm line 1.
BEGIN failed--compilation aborted at lib/File/Find.pm line 1.
Compilation failed in require at /home/hakon/perl5/lib/perl5/App/Prove/State.pm line 6.
BEGIN failed--compilation aborted at /home/hakon/perl5/lib/perl5/App/Prove/State.pm line 6.
Compilation failed in require at /home/hakon/perl5/lib/perl5/App/Prove.pm line 10.
BEGIN failed--compilation aborted at /home/hakon/perl5/lib/perl5/App/Prove.pm line 10.
Compilation failed in require at /home/hakon/perl5/bin/prove line 8.
BEGIN failed--compilation aborted at /home/hakon/perl5/bin/prove line 8.
The spawned process exited unsuccessfully (exit code: 255)
After subsequent input from #gfldex I tried to remove package
rakudo. Maybe the presence of the binary /usr/bin/perl6 would cause confusion for the installer:
> sudo apt-get remove rakudo
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
libparrot6.6.0 linux-headers-4.2.0-16 linux-headers-4.2.0-16-generic linux-headers-4.2.0-27 linux-headers-4.2.0-27-generic linux-image-4.2.0-16-generic
linux-image-4.2.0-27-generic linux-image-extra-4.2.0-16-generic linux-image-extra-4.2.0-27-generic nqp parrot parrot-minimal
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
rakudo
0 upgraded, 0 newly installed, 1 to remove and 6 not upgraded.
After this operation, 38,8 MB disk space will be freed.
Do you want to continue? [Y/n] Y
(Reading database ... 318170 files and directories currently installed.)
Removing rakudo (2014.07-4build1) ...
Processing triggers for man-db (2.7.4-1) ...
Then testing if the package was removed successfully:
> pwd
/home/hakon/install_rakudo/rakudo-star-2016.01
> which perl6
./perl6
> perl6 --version
This is Rakudo version 2016.01.1 built on MoarVM version 2016.01
implementing Perl 6.c.
> cd ..
> perl6 --version
The program 'perl6' is currently not installed. You can install it by typing:
sudo apt-get install rakudo
> cd rakudo-star-2016.01
Then I retried make install, but it fails with exactly the same error message as before.
Then I tried a complete reinstallation:
cd ..
rm -rf rakudo-star-2016.01/
wget http://rakudo.org/downloads/star/rakudo-star-2016.01.tar.gz
tar xzf rakudo-star-2016.01.tar.gz
cd rakudo-star-2016.01
perl Configure.pl --backend=moar --gen-moar
make
make install
But I still get the same error message from make install.
Then I tried reinstalling Panda manually once more
cd ..
git clone --recursive git://github.com/tadzik/panda.git
cd panda
../rakudo-star-2016.01/perl6 bootstrap.pl
But that also fails with the same error message (Perl v6.0.0 required--this is only v5.20.2).

Answer 1

According to user RabidGravy on IRC channel #perl6 on irc.freenode.net:
the problem with installing panda there is due to PERL5LIB or PERLLIB
being set in the environment
So now I tried clearing PERL5LIB before installing:
PERL5LIB= make install
and it worked fine.
And finally, I had to add the following paths to my ~/.bashrc to complete the setup:
/home/hakon/install_rakudo/rakudo-star-2016.01/install/bin
/home/hakon/install_rakudo/rakudo-star-2016.01/install/share/perl6/site/bin
(It would be nice to know why it was necessary to clear PERL5LIB, tough.)