Can't programmatically require() module inside phasers (Cannot invoke this object (REPR: Null; VMNull))

[p6rt]

Migrated from rt.perl.org#129109 (status was 'open')

Searchable as RT129109$

[p6rt]

From clifton.wood@gmail.com

Attempting this from the commandline will trigger this already known issue​:

$ perl6 -Ilib -e 'my @​r; BEGIN { @​r = <Test>; }; INIT { require :​:("$_") for @​r };'

===SORRY!===
Cannot invoke this object (REPR​: Null; VMNull)

See also​:

https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129096

[p6rt]

From clifton.wood@gmail.com

Can someone move this to the perl6 queue, please.

Thanks.

On Sat Aug 27 21​:24​:25 2016, clifton.wood@​gmail.com wrote​:

Attempting this from the commandline will trigger this already known
issue​:

$ perl6 -Ilib -e 'my @​r; BEGIN { @​r = <Test>; }; INIT { require
:​:("$_") for @​r };'

===SORRY!===
Cannot invoke this object (REPR​: Null; VMNull)

See also​:

https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129096

[p6rt]

From [Unknown Contact. See original ticket]

Can someone move this to the perl6 queue, please.

Thanks.

On Sat Aug 27 21​:24​:25 2016, clifton.wood@​gmail.com wrote​:

Attempting this from the commandline will trigger this already known
issue​:

$ perl6 -Ilib -e 'my @​r; BEGIN { @​r = <Test>; }; INIT { require
:​:("$_") for @​r };'

===SORRY!===
Cannot invoke this object (REPR​: Null; VMNull)

See also​:

https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129096

[p6rt]

From @cpansprout

On Sat Aug 27 21​:28​:37 2016, clifton.wood@​gmail.com wrote​:

Can someone move this to the perl6 queue, please.

Done.

--

Father Chrysostomos

[p6rt]

The RT System itself - Status changed from 'new' to 'open'

[p6rt]

From @masak

<Xliff_> require Color if $colorSupport;
<Xliff_> ==> Cannot invoke this object (REPR​: Null; VMNull)
* Xliff_ pulls hair.
<masak> Xliff_​: if you can golf that, we might have something to rakudobug.
<Xliff_> masak​: Already done.
<Xliff_> https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129109
<masak> reproduced locally.
<masak> $ perl6 -Ilib -e'my $colorSupport = True; require Color if $colorSupport; say "hi"'
<masak> ===SORRY!===
<masak> Cannot invoke this object (REPR​: Null; VMNull)
<Xliff_> I'm now thinking it has nothing to do with phasers and everything to do with programatic require.
* masak adds the case with the `if` statements to that ticket

[p6rt]

From @ugexe

$ perl6 -e 'my $module-support = BEGIN (try require :​:("Test")) !~~ Nil; INIT { if $module-support { require :​:("Test"); }; }; say ?$module-support ?? :​:("Test").perl !! "Failed to load"'

Test

$ perl6 -e 'my $module-support = BEGIN (try require :​:("XXX")) !~~ Nil; INIT { if $module-support { require :​:("XXX"); }; }; say ?$module-support ?? :​:("XXX").perl !! "Failed to load"'

Failed to load

[p6rt]

From @zostay

I ran into what I believe is this problem while working on some code that loads a Perl 6 CompUnit provided by the end-user. No phasers are involved. I am just running require :​:("...") very late in the program.

I wrote CompUnit​::DynamicLib to help out with what I'm doing. With that library I can include some custom code like this​:

require-from <custom/path/lib>, $class-name;
my $obj = :​:($class-name).new;

However, I started getting "Cannot invoke this object (REPR​: Null; VMNull)". I was able to work around the issue by changing the code inside of CompUnit​::DynamicLib from this​:

require :​:($module-name);

to this​:

# Work-around RT #​129109
# require :​:($module-name);
# TODO Try removing this work-around once the ticket is resolved.
use MONKEY-SEE-NO-EVAL;
EVAL "use $module-name";

That's a slightly ugly work-around to the issue until this gets fixed. I don't know what require is failing to do that EVAL "use..." does, but maybe that provides a hint to the fixer as well.