[perl #127694] REPL -I does not add path to $*REPO

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# New Ticket Created by  Yary 
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# <URL: https://rt.perl.org/Ticket/Display.html?id=127694 >


I've cloned a module from GitHub into a local directory, but can't load it in 
the REPL using the -I command line argument.

Example, using -e and not using the REPL, which works:

  perl6 -I c:\Users\yhluc00\Documents\GitHub\grammar-generative\lib -e "use 
Grammar::Generative; say 'Alive'"
    Alive

The above, using the REPL:

  perl6 -I c:\Users\yhluc00\Documents\GitHub\grammar-generative\lib
You may want to `panda install Readline` or `panda install Linenoise` or use 
rlwrap for a line editor

  use Grammar::Generative;
Could not find Grammar::Generative in:
    C:\Users\yhluc00\AppData\Roaming\.perl6\2016.01.1
    C:\rakudo\share\perl6\site
    C:\rakudo\share\perl6\vendor
    C:\rakudo\share\perl6
    CompUnit::Repository::AbsolutePath<109859840>
    CompUnit::Repository::NQP<104208984>
    CompUnit::Repository::Perl5<104209024>
  in any load_module at src/Perl6/World.nqp line 978
...

Note that the path given to -I is not in the list of paths shown in the error 
message.

I expected the REPL to respect the "-I" argument, and any other command-line 
arguments, to the extent that a REPL can. But maybe my expectation is missing a 
good reason to filter out all command-line args from the REPL's environment. Is 
this a REPL bug or a problem with my understanding?