Hi All, I'm confused about a namespace issue when using Safe. According to the documentation, code executed within a Safe compartment believes that it resides in package main, when in fact it is in a special namespace of $Safe::Root0 (or another name of your choosing). Now, using B::Deparse::coderef2text will return a bare block where the first statement is a package statement reflecting the package in which the code was originally compiled. Something like: 

{
 package Foo;
 print "Hello World\n";
}

[download]

When running this B::Deparse'd code through Safe::reval, I'd expect the code then to execute within Safe::Root0::Foo. However, as the below example shows, the code thinks it is in package main, as the documentation of Safe says code ought to. Does this mean that package statements in Safe::reval'd strings are wholly ignored, thereby making it pointless to remove them, or is the code actually in Safe::Root0::Foo but believes it's in main? 

Package Foo;
sub new {
    my $class = shift;
    my $this = bless {}, $class;
    $this->_init();
    return $this;
}

sub _init {
    my $cpt = new Safe();
    my $s = sub {eval q/print "PACKAGE is ",__PACKAGE__,"\n"/; };

    # explicitly permit use of 'eval'
    $cpt->permit('entereval');

    my $deparse = B::Deparse->new();

    # prepend 'sub' so we have an anonymous sub later
    my $code_str = 'sub '.$deparse->coderef2text($s);

#   Seems to have no effect on behavior to remove package statements
#    $code_str =~ s/package \w+\;//g;
    print "DEPARSED $code_str\n";

    my $result = $cpt->reval($parsed);
    die $@ if $@;
    $result->();   

}

[download]
Output: "PACKAGE is main"

Many thanks, fever

In reply to Safe, namespaces, B::Deparse by djantzen

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