Using ‘return’ in a Ruby block

Simply use next in this context:

$ irb
irb(main):001:0> def thing(*args, &block)
irb(main):002:1>   value = block.call
irb(main):003:1>   puts "value=#{value}"
irb(main):004:1> end
=> nil
irb(main):005:0>
irb(main):006:0* thing {
irb(main):007:1*   return 6 * 7
irb(main):008:1> }
LocalJumpError: unexpected return
        from (irb):7:in `block in irb_binding'
        from (irb):2:in `call'
        from (irb):2:in `thing'
        from (irb):6
        from /home/mirko/.rvm/rubies/ruby-1.9.1-p378/bin/irb:15:in `<main>'
irb(main):009:0> thing { break 6 * 7 }
=> 42
irb(main):011:0> thing { next 6 * 7 }
value=42
=> nil
  • return always returns from method, but if you test this snippet in irb you don’t have method, that’s why you have LocalJumpError
  • break returns value from block and ends its call. If your block was called by yield or .call, then break breaks from this iterator too
  • next returns value from block and ends its call. If your block was called by yield or .call, then next returns value to line where yield was called

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