> On Mon, Jun 25, 2001 at 06:13:18PM -0400, Richard J. Barbalace wrote:
>
> > I'm writing a package that uses another module. This latter module may
> > change somewhat erratically and unreliably, outside of my control. As
> > a result, I want to have the package test itself and die if it notices
> > that the other module has changed in an incompatible way. What's a
> > good way of doing this?
Paul Johnson writes:
> What's wrong with just sticking your test at the end of the module? Any
> code found "lying around" in the module will be run as soon as the
> module is compiled. This is useful for initialising the module, or
> possibly testing it ....
That works if you return to the same package. For example, if I had a
main package and several sub-packages that inherited from it, the
following works without giving any warning:
package MyPackage;
use Flakey;
.....
package MyPackage::A;
use vars qw( @ISA );
@ISA = qw(MyPackage);
.....
package MyPackage::B;
use vars qw( @ISA );
@ISA = qw(MyPackage);
.....
package MyPackage::C;
use vars qw( @ISA );
@ISA = qw(MyPackage);
.....
package MyPackage;
# Test if Flakey is compatible with MyPackage
This works fine if you only need to verify the main package. (And
actually, in my current case I think I can get away with that.) But
I'm also interested in the more general case of testing the
sub-packages as well.
Trying to do this gives a warning. For example:
package MyPackage;
use Flakey;
.....
package MyPackage::A;
.....
package MyPackage::C;
# Test if Flakey is compatible with MyPackage::C
use MyPackage; # Required since we're not in MyPackage
If I want to test each of the sub-packages, I have to "use MyPackage"
(or something equivalent). Initially I thought the warnings might
result because "use" is really a BEGIN block, but replacing it with
"require" and "import" statements cause other problems.
+ Richard
