Jensen's device

In article 98-03-193,


> [Remember that call by name was a mistake. The Algol60 was trying to write
> an elegant definition of call by reference and inadvertently created call
> by name. Nobody realized it until the paper on Jensen's device. -John]


This is very interesting. I didn't know about this before (except of Jensen's
device, of course). Well, I have a few questions about this stuff. Could
someone answer them, please?


1. When they discovered the mistake, why didn't they simply rewrite the
      document containing the definition of Algol-60? I assume, it was not
      so easy because of all that bureaucratic work :-(


2. When this mistake was discovered, were any Algol-60 compilers already
      out there? If so, how was this kind of parameter passing implemented
      in them?


3. Could someone provide me with a reference to the paper, in which Jensen's
      device was first described? Is this paper written by Mr. Jensen himself,
      or by someone else?


4. Who is Mr. Jensen, when and how he discovered his famous "device"?


Thanks.


                                                                                      Andrejs.
[By the time Jensen's discovery came to light, I believe in a letter
or article in the CACM, the Algol report had been done for a couple of
years. I don't know whether there were compilers that used
call-by-reference which had to be changed -- Algol60 was more a
publication language than a day-to-day programming language. Al
Perlis, who wrote the Algol 60 report, told me about the mistake, but
he's no longer around to fill in the details. -John]


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