Question

Is there any way to access object from block which was defined inside different scope? Sorry if it’s confusing, I provide a little example:

def scope(&block)
  foo = "bar"
  instance_eval &block
end

scope do
  puts "foo is #{foo}"
end

I’d like to get the output:

"foo is bar"

Is it possible?

Answer 1

The real question is what you’re trying to do, but the closest you can get is this:

def scope
  @foo = "bar"
  yield
end

scope do
  puts "foo is #{@foo}"
end

Note the use of an instance variable @foo instead of a local variable. You can’t access the instance variable unless you do so explicitly, like this:

def scope
  foo = "bar"
  yield foo
end

scope do |foo|
  puts "foo is #{foo}"
end

But this is good. Otherwise it would be difficult to avoid conflicts with your local variables.

Note: I’ve also replaced your use of an explicit &block with the implicit yield. The yield form requires a block to be present, and has a simpler syntax, but it is largely a matter of style.