So part of the problem (apart from my inability to get this to work at all) is that the warn statements are outside the $code->() call. Is there a way I can append them inside the subroutine itself?

You may find interesting this post. You can edit the source of the subroutines and evaluate it into code again:

use B::Deparse;

sub something {
    my ( $self, $param ) = @_;
    return _stuff($param);
}

my $subref = \&something;
my $code = B::Deparse->new->coderef2text($subref);
print "Before editing &something:\n",$code;
$code =~ s/\{/\{\nlog_msg('starting sub');\n/;
*something = eval "sub $code";

$code = B::Deparse->new->coderef2text(\&subref);
print "\nAfter editing &something:\n",$code;

[download]

Outputs:

Before editing &something:
{
    use warnings;
    use strict 'refs';
    my($self, $param) = @_;
    return _stuff($param);
}
After editing &something:
{
    use warnings;
    use strict 'refs';
    log_msg('starting sub');
    my($self, $param) = @_;
    return _stuff($param);
}

[download]

Hope this helps

citromatik

In reply to Re: Rewriting sub code on import to add logging by citromatik
in thread Rewriting sub code on import to add logging by gryphon

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