Friday, July 12, 2013

[ruby] Calling :methods on BasicObject

So, I just learnt a couple of days ago that you could pass in false to  :methods , and it'll filters out the inherited methods and return an array of only the methods that are defined in the class.
And as I spent time playing with it, I thought I'll check how BasicObject would respond to, if I called methods(false) on it.

My assumption was that BasicObject would possibly be the only class which would return back the same array for :methods(true) and :methods(false) - since it doesn't inherit from anything.

So here's what I did

BasicObject.methods(false) # => []

An empty array? Given that BasicObject is the root of Ruby's object hierarchy, it didn't make sense that BasicObject could respond differently for :methods(true) and :methods(false) - So where were those methods coming from?

After a few mins of trying to Google, I reached out to [Chew Choon Keat]( and he figured the obvious problem here. It wasn't BasicObject responding to the call - The receiver was instead a Class object.

:instance_methods seems to be respond like how I expected it to though.

Oh, and :methods is defined in the Kernel module, that gets included into Object class.


Thursday, July 11, 2013

RVM install fails when you have developer preview of xcode5 installed

I was just installing ruby-2.0.0-p247 on my machine (high time, I know!), and rvm kept failing silently.  It would download ruby, extract, proceed till configure, and failed at the installation phase.

So I ran

rvm install --debug ruby-2.0.0-p247 

And this exposed the location of the installation log file.  

The log, showed that the failure was with a missing path within - 

Apple's Xcode5 developer preview app 1 & 2 were just named, but with the Developer preview 3, the app's called - And for some reason rvm's install scripts were looking for a path inside Strange.

Anyway, I then proceeded to symlink as, did a rvm install again, and this time, installation went smooth.

Blogging this, just in case someone else runs into the same issue. I can't be the only one who's so late to the party?