----- Original Message -----
From: "Robert H" <sigz...@gmail.com>
To: <inline@perl.org>
Sent: Wednesday, September 16, 2009 11:28 AM
Subject: XS vc Inline
When would you not use Inline instead of doing it with XS? For example, I
am thinking about doing a wrapper for Metakit (ie DBD::Metakit). I talked
with the author of Metakit and he said he tried to do a Perl wrapper in XS
once but got lost. Is it feasible to do something like that using Inline
instead or would XS be the best case scenario for a DBD module?
Both approaches are feasible - Inline::C is, after all, just a means of
auto-generating an XS file. It does a little more than that, of course - it
also compiles the XS code it created, and then runs the script (which
usually makes use of that XS code).
The tricky bit (and this may well be where the author "got lost") is often
in the way the Perl API meets the library that you want to wrap, and you
face the same challenges in that regard whether it's an Inline::C script or
an XS file that you're trying to write.
For modules, I have a preference for XS, rather than Inline::C - but I don't
have any really compelling reasons for that preference. I think there might
still be issues if one Inline::C module tries to use another Inline::C
module (not sure) .... and I like to keep pre-requisites to a minimum ....
and XS just seems cleaner to me for modules .... but, as I said, nothing
compelling.
Inline::C does provide a nice "test it as-you-go" facility, so if you think
that might make the task easier, by all means do it in Inline::C. When it's
all done, if you want, you can convert your Inline::C code to XS code by
running it through InlineX::C2XS (which uses Inline::C to autogenerate the
XS code from your Inline::C code). InlineX::C2XS will also write a
Makefile.PL and stub pm file for you if you want. (The test scripts that
you've written to go with the Inline::C module can be used without
modifcation with your XS distro, if you decide to make the switch.)
All XS modules that I have written start off as Inline::C code (mainly
because I need to "test it as-I-go"), and then the XS file gets written by
InlineX::C2XS when everythng is working as it should.
Cheers,
Rob
