Monthly Archives: January 2012

extconf.rb:4:in `require’: no such file to load — mkmf (LoadError)

Posted on January 20, 2012 by force

I’ve hit this a dozen times and I always forget the solution. When you get this on Ubuntu, sudo apt-get install ruby-dev

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ssh Through Two Hosts in One Command

Posted on January 19, 2012 by force

Say you want a shell on a box but you have to hop through another box to get it. force@harold:~% ssh admin@maude maude:~ force$ ssh root@whee root@whee:~$ echo w00t w00t You can do that in one line using -t (pseudo-tty … Continue reading →

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JavaScript Performance: Iterating over Arrays with Holes

Posted on January 12, 2012 by force

I was sketching some code that basically took some data from a database and cached it in an array to be repeatedly reused. Conveniently, each row from the database had a unique ID, so I could use that as an … Continue reading →

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Defining Functions Inline Is Just Fine

Posted on January 4, 2012 by force

I put together this jsperf to see if there’s a difference between defining your function and then using it or defining it inline when looping with jQuery.each. You can try it yourself if you like, but here are the results: … Continue reading →

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