Scope issue of variable in iterator


#1

mkhan@mkhan:~$ irb
irb(main):001:0> batman = ‘robin’
=> “robin”
irb(main):002:0> [ ‘cat’, ‘dog’, ‘horse’, ‘chicken’ ].each { |batman|
puts batman }
cat
dog
horse
chicken
=> [“cat”, “dog”, “horse”, “chicken”]
irb(main):003:0> puts “Now you might think this would say ‘robin’, but
it says: #{batman}”
Now you might think this would say ‘robin’, but it says: chicken
=> nil
irb(main):004:0>


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#2

On 3/22/06, Mohammad K. removed_email_address@domain.invalid wrote:

irb(main):003:0> puts “Now you might think this would say ‘robin’, but
it says: #{batman}”
Now you might think this would say ‘robin’, but it says: chicken
=> nil

It’s true that blocks introduce a new scope.
However, if they use variables that are in scope outside the block,
they don’t shadow those variables, they use them.


#3

Mark V. removed_email_address@domain.invalid wrote:

=> [“cat”, “dog”, “horse”, “chicken”]
irb(main):003:0> puts “Now you might think this would say ‘robin’,
but it says: #{batman}”
Now you might think this would say ‘robin’, but it says: chicken
=> nil

It’s true that blocks introduce a new scope.
However, if they use variables that are in scope outside the block,
they don’t shadow those variables, they use them.

… like in other programming languages as well.

robert