Today in Computational Necromancy: MOST-POSITIVE-BIGNUM, redux

In 1990, I did a hack to compute the largest representable integer on a system that purportedly had no upper bound on that.

In 2008, I wrote about it.

In 2018, someone ran my code and sent me screenshots!

This person got their hands on a gloriously-vintage TI MicroExplorer -- that's a Lisp Chip on a NuBus card, using a Mac IIfx as little more than a device driver for the screen and keyboard.

And a mere 20 hours later,
Exhibit B:

Remember, kids! If it runs Emacs, it's a computer. Otherwise, it's a peripheral.

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12 Responses:

  1. Philip Guenther says:

    The best part is the "**MORE**" in the second screenshot. "I spent twenty hours converting that to decimal and I'm ready to stuff it down your eyeballs, one page at a time, goddamnit!"

    • jwz says:

      Many are the mornings that I came in to see an overnight run blocked at **MORE**. The terminal wasn't in a separate process with a text buffer between the two. That prompt halted everything until you hit space.

      • Philip Guenther says:

        "Your output buffer fills; your process is petrified -- more --"
        "your process makes its saving throw and resumes"

        Worst Rogue-like Ever.

  2. White Flame says:

    And today with SBCL, (time (length (write-to-string (ash 1 (* 31 (1- (ash 1 17))))))) takes 6.002 seconds. :)

  3. Buddy Casino says:

    The real wtf here is having 12MB of physical memory in 1990.

    • tfb says:

      My memory of things that long ago is fading, but 12MB sounds plausible: the Sun 3/50 I had a year or so earlier had 4 which was not enough, the 4/65s had, I think, 16, and bigger 4s had maybe 24 or 32.

  4. Logan Bowers says:

    Your essay hating on the Java ecosystem 20 years ago is hilariously still on point.

    • jwz says:

      It's a hate flower that blooms all year. I'm glad I get to 100% ignore it now. I think the only reason my machine even has a Java runtime installed is because Illustrator inexplicably still requires it.

  5. jwz says:
    Some code I wrote in 1989, when fractals were monochrome:

    30 seconds of MOST-POSITIVE-BIGNUM scrolling by.
    The whole thing takes about 10 minutes.

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