instance method LocalJumpError#reason

例外を発生させた原因をシンボルで返します。

返す値は以下のいずれかです。

• :break
• :redo
• :retry
• :next
• :return
• :noreason

def foo
  proc { return 10 }
end
  
begin
  foo.call
rescue LocalJumpError => err
  p err              # => #<LocalJumpError: unexpected return>
  p err.reason       # => :return
end

begin
  Proc.new { break 5 }.call
rescue LocalJumpError => err
  p err              # => #<LocalJumpError: break from proc-closure>
  p err.reason       # => :break
end