From: Devin Mullins <twifkak@...>
Date: 2005-06-27T10:50:08+09:00
Subject: Re: newbie scope question

Wow, that was a simple and complete summary of scope in Ruby. That helps 
a lot. :)

I had known that variables defined inside blocks didn't escape blocks. I 
didn't know that the same wasn't true for loops and conditionals. 
Essentially, scope is flat inside a class/module/method, with the odd 
exception of blocks.

This is good, except it makes blocks a little confusing

Example #1:
irb(main):001:0> a = nil
=> nil
irb(main):002:0> 5.times {|a| }
=> 5
irb(main):003:0> a
=> 4

Example #2:
irb(main):006:0> 5.times {
irb(main):007:1*   a ||= 0
irb(main):008:1>   a+=1
irb(main):009:1>   print a, ' '
irb(main):010:1> }
1 1 1 1 1

Example #3:
irb(main):001:0> a = 0
=> 0
irb(main):002:0> 5.times {
irb(main):003:1*   a ||= 0
irb(main):004:1>   a+=1
irb(main):005:1>   print a, ' '
irb(main):006:1> }
1 2 3 4 5

Not a huge issue. Just something to get used to.

Devin