From: Xeno Campanoli <xcampanoli@...>
Date: 2007-07-07T04:20:34+09:00
Subject: hpricot won't install on Ubuntu and complains because mkmf.rb is missing

I have mechanize installed on Feisty, which has Ruby 1.8.5, but when I
just tried to install it on Gutsy, which has 1.8.6, I got the following:

root@joehill:~# gem install mechanize
Install required dependency hpricot? [Yn]
Select which gem to install for your platform (i486-linux)
 1. hpricot 0.6 (mswin32)
 2. hpricot 0.6 (jruby)
 3. hpricot 0.6 (ruby)
 4. hpricot 0.5 (ruby)
 5. hpricot 0.5 (mswin32)
 6. Skip this gem
 7. Cancel installation
> 3
Building native extensions.  This could take a while...
ERROR:  While executing gem ... (Gem::Installer::ExtensionBuildError)
    ERROR: Failed to build gem native extension.

ruby extconf.rb install mechanize
extconf.rb:1:in `require': no such file to load -- mkmf (LoadError)
        from extconf.rb:1


Gem files will remain installed in
/usr/lib/ruby/gems/1.8/gems/hpricot-0.6 for inspection.
Results logged to
/usr/lib/ruby/gems/1.8/gems/hpricot-0.6/ext/hpricot_scan/gem_make.out
root@joehill:~#
---snip---
If this is a problem with the Ruby install on Gutsy/Ubuntu, please
explain that so I can bug it on Launchpad.  Thanks.

xc
-- 
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but on good design of the functional unit,
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