Re: Dynamically Changing Packages w/out Eval

Some funny code I wrote yesterday (the technique can be probably used for your problem too):

use Symbol qw(qualify_to_ref);
use overload;
my $stashref = qualify_to_ref("${namespace}::");

package tmp;
local *tmp:: = *$stashref;
overload->import('+' => sub {
     my $self = shift;
     my ($other, $info) = @_;
     # do some stuff
});
[download]

This sets up overloaded operators for the namespace with the computed name $namespace.

Note that you cannot use "main" instead of "tmp", because the main namespace seems to be too read-only for this kind of hack (you'd get the error "Modification of read-only value attempted")

Comment on Re: Dynamically Changing Packages w/out Eval Select or Download Code

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Re^2: Dynamically Changing Packages w/out Eval by ikegami (Patriarch) on Aug 24, 2009 at 13:41 UTC
A lot simpler and a lot less fragile: `my @overload = ('+' => sub { my $self = shift; my ($other, $info) = @_; # do some stuff }); eval "package $namespace; use overload \@overload; 1" or die $@;` [download]	[reply] [d/l]
Re^3: Dynamically Changing Packages w/out Eval by betterworld (Curate) on Aug 24, 2009 at 14:13 UTC
I thought the original question was how to avoid eval :)	[reply]
Re^4: Dynamically Changing Packages w/out Eval by ikegami (Patriarch) on Aug 24, 2009 at 14:43 UTC
True, but he wanted to avoid `eval` "because it obfuscates the code". It's clearly the opposite here.	[reply] [d/l]
Re^5: Dynamically Changing Packages w/out Eval by betterworld (Curate) on Aug 24, 2009 at 19:54 UTC
Re^6: Dynamically Changing Packages w/out Eval by ikegami (Patriarch) on Aug 24, 2009 at 21:35 UTC
Re^4: Dynamically Changing Packages w/out Eval by Anonymous Monk on Aug 24, 2009 at 14:15 UTC
You can't expect someone to read the OP	[reply]


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