h4x   The useless ramblings of a web developer.

After updating rails from 2.0.2 to 2.2.2 on the bit-tech CMS this week I discovered a bug that had cropped up in one of my controllers where I was calling zip to join a a has_many collection with a couple of arrays and iterate through them. The code that was working fine now did something like the following.

>> g.groups.zip([1,2], [3,4]) {|a,b,c| p a.inspect + ‘, ‘ + b.inspect + ‘, ‘ + c.inspect }
“[#<Group id: 1>, 1, 3], nil, nil”
“[#<Group id: 2>, 2, 4], nil, nil”

This is strange, I can no longer access the three elements of the array directly in the block. So I tried the following

>> g.groups.to_a.zip([1,2], [3,4]) {|a,b,c| p a.inspect + ‘, ‘ + b.inspect + ‘, ‘ + c.inspect }
“#<Group id: 1>, 1, 3″
“#<Group id: 2>, 2, 4″

As you can see this solved the problem, but I was confused why there was a difference so I executed…

>> g.groups.class
=> Array

Why when I cast it to an Array, from an Array, is it acting differently? Rails must have done something to the Array class that is returned by the has_many relationship.

Rails and rjs templates are the best thing ever!

Do a remote AJAX call from your page and in the linking controller’s view folder have a template called #{action_name}.rjs

In your rjs template you write code in ruby which is translated into javascript which can control your page content. So you can replace html, insert partials and do page effects.