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Nailed by two coding gotchas in two days. Argh!

Here’s the one in Javascript.

js> var a = (100).toFixed(2);
js> a
100.00
js> var b = (20).toFixed(2);
js> b
20.00
js> a > b
false

a is 100.00, and b is 20.00. 100.00 is greater than 20.00 right? Yes, except that they’re strings! toFixed returns strings, and any comparison is a string comparison and not a numeric comparison!

Now, here’s the Ruby one that got me. If you’re not a Ruby person then this one might be a little harder to pick.

irb(main):001:0> class Klass
irb(main):002:1>   def meth=(value)
irb(main):003:2>     return 'return this please'
irb(main):004:2>   end
irb(main):005:1> end
=> nil
irb(main):006:0>
irb(main):007:0* obj = Klass.new
=> #<Klass:0x83180>
irb(main):008:0> obj.meth = "Do not return this please"
=> "Do not return this please"

Well, I wanted to return “return this please” on the assignment, but instead Ruby ignored me and returned the value of the assignment instead. What if I want to indicate that the assignment failed? My only option is to throw an exception.

I can appreciate that Ruby wants to keep things consistent and always return the assignment value, but can Ruby appreciate my view of consistency and return when I say to return!

If you can tell me why Ruby behaves this way I would appreciate it if you could leave your mark in my comments section.