# Re: Ruby extension tutorial **URL:** \ **Category:** Ruby\ **Created:** [January 22, 2007, 1:15am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866 "2007-01-22T01:15:31Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 1:15am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/1 "2007-01-22T01:15:31Z")
Wim Vander S. schreef: > kind regards, > > Wim Silly me, I forgot to paste the link, here you go: [http://nanoblog.ath.cx/index.rb?module=readmore&id=8](http://nanoblog.ath.cx/index.rb?module=readmore&id=8) - Wim ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 1:24am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/2 "2007-01-22T01:24:32Z")
Hey Wim, Change “fase” to “phase”. Also, I think there is a typo in the opening. Where you say “Ruby is slow”, I think what you mean is “Ruby is an extremely powerful and flexible language”. It’s an understandable mistake, all of the keys are so close to each other. 😉 Thanks for the section and examples on Ruby mark-and-sweep, this is something I’ve been having some trouble with. Garth Wim Vander S. wrote: > Wim Vander S. schreef: > > > Hi, > > > > I just finished a tutorial about writing simple ruby extensions. > > I was hoping you guys could give me some feedback on what you think > > about it. > > > > If you find any mistakes (code, spelling, grammar and explanation), > > I > > would also appreciate it if you told me about them? > > > > I’m looking for critisism - I hope to improve the article. > > > > kind regards, > > > > Wim > > Silly me, I forgot to paste the link, here you go: > > [http://nanoblog.ath.cx/index.rb?module=readmore&id=8](http://nanoblog.ath.cx/index.rb?module=readmore&id=8) ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 2:10am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/3 "2007-01-22T02:10:36Z")
I like the content of the tutorial, and I’ve been curious about writing C extensions for a while. One thing, though, is that I believe you have misspelled phase and fase. Dan ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 2:21am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/4 "2007-01-22T02:21:37Z")
Wim Vander S. wrote: > > I’m looking for critisism - I hope to improve the article. > > Nice work! Here’s a couple of nitpicks… You recommend using the “rb\_” prefix on classes, modules, etc., but I’d argue that rb\_-prefixed names should be reserved for things defined by Ruby itself, and your extension should use some other naming convention. You use names\_array-\>ptr[i] to access elements in an array. My choice would be to use rb\_ary\_index instead, to put a little logical distance between my code and the RArray structure definition. You could use rb\_ary\_length to get the array size as well. Regarding “Where to go from here,” another good learning resource is the C sources for the builtin classes. I frequently refer to string.c, array.c, io.c, etc. to see how things should be done. ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 9:40am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/5 "2007-01-22T09:40:22Z")
Thank you all for your comments! > Change “fase” to “phase”. > Doh. Changed. > > Also, I think there is a typo in the opening. Where you say > “Ruby is slow”, I think what you mean is “Ruby is an extremely > powerful and flexible language”. It’s an understandable mistake, > all of the keys are so close to each other. 😉 > I fixed that, that always happens to me, my keyboard must have been low > on batteries > > Thanks for the section and examples on Ruby mark-and-sweep, this > is something I’ve been having some trouble with. > Your welcome 🙂 > You recommend using the “rb\_” prefix on classes, modules, etc., but > I’d argue that rb\_-prefixed names should be reserved for things > defined by Ruby itself, and your extension should use some other > naming convention. > You’re right, I’ve changed that now. > You use names\_array-\>ptr[i] to access elements in an array. My choice > would be to use rb\_ary\_index instead, to put a little logical distance > between my code and the RArray structure definition. You could use > rb\_ary\_length to get the array size as well. > Hmmm I never even heard of that, would probably be better. I’ll look > into it after my exams, and if I like it, I’ll change it. > Regarding “Where to go from here,” another good learning resource is > the C sources for the builtin classes. I frequently refer to string.c, > array.c, io.c, etc. to see how things should be done. > You’re right, I added that. > One item on my wishlist would be to show (in perhaps a sidebar) how to > use mkrf instead of mkmf. I haven’t heard of mkrf yet, but I’ll also check that out after my exams. Thanks for the suggestion. Wim ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 10:46am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/6 "2007-01-22T10:46:32Z")
Eric H. schreef: > cleanly in extconf.rb. > > –Eric H. - removed\_email\_address@domain.invalid - [http://blog.segment7.net](http://blog.segment7.net) > > I LIT YOUR GEM ON FIRE! Yes, I first did that as well, I thought have\_header and the like aborted all by themselves. I changed it to abort ‘need stdio.h’ now, looks cleaner when it fails. Kind regards, Wim ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 11:05am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/7 "2007-01-22T11:05:35Z")
On Jan 22, 2007, at 01:46, Wim Vander S. wrote: > Eric H. schreef: > > > I’d change this to: > > > > abort ‘need stdio.h’ unless have\_header(“stdio.h”) > > Yes, I first did that as well, I thought have\_header and the like > aborted all by themselves. I changed it to abort ‘need stdio.h’ > now, looks cleaner when it fails. It allows you to look for headers that may have different names for different versions like: have\_header “foo1.h” or have\_header “foo2.h” or abort “can’t find headers for foo” – Eric H. - removed\_email\_address@domain.invalid - [http://blog.segment7.net](http://blog.segment7.net) I LIT YOUR GEM ON FIRE! ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 10:20am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/8 "2007-01-22T10:20:30Z")
On Jan 21, 2007, at 16:10, Wim Vander S. wrote: > Wim Vander S. schreef: > > > I just finished a tutorial about writing simple ruby extensions. > > I was hoping you guys could give me some feedback on what you > > think about it. > > > > If you find any mistakes (code, spelling, grammar and > > explanation), I would also appreciate it if you told me about them? > > [http://nanoblog.ath.cx/index.rb?module=readmore&id=8](http://nanoblog.ath.cx/index.rb?module=readmore&id=8) > exit unless have\_header(“stdio.h”) I’d change this to: abort ‘need stdio.h’ unless have\_header(“stdio.h”) but other than that, thank you, thank you, thank you for using an example that doesn’t proceed to write a Makefile when the right thingies aren’t found. I think about half the C extensions I’ve installed puke somewhere after attempting to build rather than puking cleanly in extconf.rb. – Eric H. - removed\_email\_address@domain.invalid - [http://blog.segment7.net](http://blog.segment7.net) I LIT YOUR GEM ON FIRE! ---
**Author:** ![Wim\_Vander\_S](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/w/13edae/32.png) [@Wim\_Vander\_S](https://www.ruby-forum.com/u/Wim_Vander_S)\ **Post date:** [January 22, 2007, 11:13am UTC](https://www.ruby-forum.com/t/re-ruby-extension-tutorial/82866/9 "2007-01-22T11:13:56Z")
Eric H. schreef: > It allows you to look for headers that may have different names for I might add this to the discussion of the extconf.rb file later, I think it deserves a little extra attention. - Wim