• @[email protected]
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    7322 hours ago

    It is true. Math.min() returns positive Infinity when called with no arguments and Math.max() returns Negative Infinity when called with no arguments. Positive Infinity > Negative Infinity.

    Math.min() works something like this

    def min(numbers):
      r = Infinity
      for n in numbers:
        if n < r:
          r = n
      return r
    

    I’m guessing there’s a reason they wanted min() to be able to be called without any arguments but I’m sure it isn’t a good one.

    • @[email protected]
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      3221 hours ago

      So, the language isn’t compiled (or wasn’t originally) so they couldn’t make min() be an error that only a developer saw, it has to be something that the runtime on the end-user system dealt with. So, it had to be assigned some value. Under those restrictions, it is the most mathematically sound value. It makes miniumum-exactly-2(x, min(<…>)) be exactly the same as min(x, <…>), even when the “<…>” has no values.

      As a developer, I see a lot of value in static analysis, including refusing to generate output for sufficiently erroneous results of static analysis, so I don’t like using JS, and the language that I tinker with will definitely have a separate compilation step and reject the equivalent of min(). But, if I HAD to assign something like that a value, it probably would be a representation of infinity, if we had one (probably will due to IEEE floats).

      HTH

      • @[email protected]
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        612 hours ago

        The language not being compiled has nothing to do with error handling. You could have a min function that operates on dynamic arrays (e.g. std::min_element in C++ or min() in Python).

        • @[email protected]
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          12 hours ago

          Not having a separate compilation step absolutely affects error handling. With a compilation step, you can have errors that will only be seen by and must be address by a developer prior to run time. Without one, the run time system, must assign some semantics to the source code, no matter how erroneous it is.

          No matter what advisory “signature” you imagine for a function, JS has to assign some run time semantics to that function being called incorrectly. Compiled languages do not have to provide a run time semantics to for signatures that can be statically checked.