Re^4: "use" modifier code via import()

I guess you never use strict, warnings, lib, CGI, or many other core modules since it would be hopelessly confusing for people to find that they weren't importing symbols into your package.

I don't know where this 'use is only for importing symbols' meme snuck in, but I've certainly never read that rule anywhere and don't assume only symbol exporting when I see a module. In fact, the meme is plain wrong.

It is certainly common for modules to primarily export symbols. It is also certainly common for subroutines to work on numbers. But there are plenty of modules that don't export symbols and it often makes sense to make it easy for the module user to pass arguments in.

In fact, I'm pretty sure that Larry and company provided the mechanism for that reason, especially since they immediately went out and used it (and not for importing symbols).

- tye

Comment on Re^4: "use" modifier code via import()

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Re: Re^4: "use" modifier code via import() by perrin (Chancellor) on May 18, 2004 at 03:17 UTC
Well, strict, warnings, and lib are all pragmas, so I don't expect them to behave the same as user-written modules. CGI mostly uses the import parameters for importing. The "pragmas" it provides could be handled in another way. The CGI interface is pretty strange, and I wouldn't hold it up as an example of something I would want others to follow. I've certainly never read that rule anywhere and don't assume only symbol exporting when I see a module. There are no rules, as we all know, but some things are more confusing than others. Sometimes people go overboard with Perl's flexibility in order to get a certain syntax that appeals to them. The core documentation on the creation of modules is nearly all about using Exporter, and the idea that a function called "import" would be doing something entirely unlike importing is not obvious to people who haven't seen it done before.	[reply]
Re: Re: Re^4: "use" modifier code via import() by hv (Prior) on May 18, 2004 at 03:40 UTC
Personally, I hate Exporter: in general, I don't want anyone stomping on my namespace, and I'm happy to fully qualify function calls and variable references (indeed, eager to, since it makes the code far clearer). To me, `import()` is about bringing in the requested functionality: typically, modifying the behaviour of the package I'm loading as a result of the arguments I supply to `use`. Any and all creative use of `import()` (properly documented, of course) is fine by me. Hugo	[reply] [d/l] [select]