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rubyblockproc

How to store ruby code blocks


I want to store a "code block" in a variable to be reused, something like:

block = do
|test| puts test
end

3.upto(8) block

Can someone show me what am I doing so obviously wrong? (Or if it's just impossible)


Solution

  • There are many ways to do this in Ruby, one of which is to use a Proc:

    foo = Proc.new do |test|
      puts test
    end
    
    3.upto(8) { foo.call("hello world") }
    

    Read more about Procs:

    Update, the above method could be rewritten as follows:

    # using lower-case **proc** syntax, all on one line
    foo = proc { |test| puts test }
    3.upto(8) { foo.call("hello world") }
    
    # using lambda, just switch the method name from proc to lambda
    bar = lambda { |test| puts test }
    3.upto(8) { bar.call("hello world") } 
    

    They're basically very similar methods, with subtle differences.

    And finally, there are probably more elegant ways to do what I've outlined, be good to hear from anyone with a better way. Hope this helps.