OO in Python is mostly pointless

Re:OO in Python is mostly pointless by throwaway894345 on Thursday January 28, 2021 @01:13PM (#25946147)

I don't usually deal with stateful closures. In OO we often have file objects, and if you call Close() on said object, subsequent Read() invocations fail because the encapsulated state has changed. What's the closure analog for this?

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Re:OO in Python is mostly pointless by lostcolony on Thursday January 28, 2021 @05:13PM (#25950164)

You've never worked with a generator before? That's a stateful function. For throwing after a file handle is closed, something like -

  const read = (fileHandle) => {
     return () => {
       if io:isOpen(fileHandle) && io:hasNext(fileHandle) => {
          return io:readNext(fileHandle)
       } else if io:isOpen(fileHandle) {return undefined
       } else {throw "File is closed"}
     } 
  }(myFile)

  read()
  read()
  io:close(myFile)
  read() //throws

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