Is this something to do with the implicit recursiveness of the main hash?

No, but "stash" is a "stash" :)( I assume a)

What you got is a typeglob, they store everything $ is 

$ perl -l -
print for $$,  ${ '::$' },  ${  $main::{ '$' }  };
&{  $main::{ '$'  }  };
__END__
2840
2840
2840
Undefined subroutine &main::$ called at - line 2.

[download]

 $ perl -e " use Data::Dump::Streamer; Dump $main::{ q{$} }; "
$VAR1 = *{'::$'};
*{'::$'} = \4032;

$ perl -e " use Data::Dump; dd $main::{ q{$} }; "
do {
  my $a = *main::$;
  $a = \2104;
  $a;
}

[download]

In reply to Re: scalar(*main::{VALUE}) appears to return a string rather than a value? by Anonymous Monk
in thread scalar(*main::{VALUE}) appears to return a string rather than a value? by Don Coyote

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