in reply to Prevent Strings From Being Interpreted As A File Handle

However, my question is: How can I disambiguate a method call on a string so that it is always resolved as a class method call, and not as a call on an IO instance?

You can't :) apparently filehandles rule the typeglob, thats why it hasn't been recommended for a long time 

$ perl -fle " sub Snacks::Ahoy { q{Nom} } open Snacks, q{>}, \q{}; pri
+nt $Snacks::{Ahoy}->() "
Nom

$ perl -fle " sub Snacks::Ahoy { q{Nom} } open Snacks, q{>}, \q{}; pri
+nt bless(\(my$q=\{Snacks}),q{Snacks})->Ahoy "
Nom

$ perl -fle " sub Snacks::Ahoy { q{Nom} } sub Snacks { q{Rice} } print
+ Snacks::->Ahoy "
Nom

$ perl -fle " sub Snacks::Ahoy { q{Nom} } open Snacks , q{<}, \q{Rice}
+; print Snacks::->Ahoy "
Can't locate object method "Ahoy" via package "IO::File" at -e line 1.

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Re^2: Prevent Strings From Being Interpreted As A File Handle
by Anonymous Monk on Apr 27, 2014 at 11:13 UTC
    disambiguation with local 
    $ perl -fle " sub Snacks::Ahoy { q{Nom} } open Snacks , q{<}, \q{Rice}
+; local *Snacks; print Snacks::->Ahoy "
Nom

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[d/l]

      This is clever. I like it.

      So we'd end up with something inconvenient like

      sub invoke_static {
    my ($class, $method, @args) = @_;
    no strict 'refs';
    # I'd like to only localize *{$class}{IO},
    # but we can't have everything, right?
    local *{$class};
    $class->$method(@args);
}

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      or something insane like

      sub safe_from_evil_filehandles(&) {
    my ($cb) = @_;
    my @evil_globs;
    ... # walk through %:: and list all globs
        # where *{$entry}{IO} is defined
        # unless they're OK like "STDOUT"
    my $localizer; $localizer = sub {
        return $cb->() unless @evil_globs;
        local *{shift @evil_globs};
        return $localizer->();
    };
    return $localizer->();
}

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[reply]
[d/l]
[select]

      This works. Good job.

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