"There doesn’t appear to be any way to undo this effect. :-("

sub foo
{
    Internals::SvREADONLY($_, 0);
    $_ = 'fred';
    goto &bar;
}

[download]

The intentionally-undocumented Internals package is part of Perl core (so much so that you don't even need to use it - it's completely internal, like parts of utf8 are) and has nothing much to do with the Internals module on CPAN.

use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^3: How to safely use $_ in a library function? by tobyink
in thread How to safely use $_ in a library function? by perl-diddler

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