• Limitless_screaming@kbin.social
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          11 months ago

          If " " wasn’t equal to 0, it wouldn’t make sense, but since a string containing a space equals 0, you’d expect the same to apply to a string containing a tab or a newline. (or at least I’d expect that)

          • FaceDeer@kbin.social
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            11 months ago

            I admit I have never dabbled in javascript, despite being a proficient programmer. I now dread to ask… would any string that contains only whitespace == 0? " \t\n \t " for example?

            • Limitless_screaming@kbin.social
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              11 months ago

              Yes, it would. Just like a string of spaces " " == 0, but it isn’t that bad; === is Javascript’s version of == in other languages, and, thus, you should be using it if you don’t want that wonkiness.

              == is just for convenience, like when you want to make sure that the user didn’t leave the form empty and the button shouldn’t be greyed out, and other UI stuff. Without these kinds of features JS wouldn’t be used in so many toolkits.

              • atx_aquarian@lemmy.world
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                11 months ago

                Ok, I always mistakenly assumed === was the identity operator in JS, too. TIL, thanks! As much as we like to poke fun at JS, every time I’m taught the rationale behind some aspect of it, I find it redeeming and even a little endearing.

                • bitcrafter@programming.dev
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                  11 months ago

                  The explanation given to you makes it sound like == was deliberately designed to be a more convenient version of ===, but what actually happened was that == used to be the only equality operator in JavaScript, which meant that if you didn’t want it’s auto-coercing behavior then you needed to go out of your way to add additional type checks yourself. Because this was obviously a tremendously inconvenient state of affairs, the === operator was introduced later so that you could test for equality without having to worry about JavaScript doing something clever underneath the hood that you weren’t expecting.

      • sbv@sh.itjust.works
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        11 months ago

        It’s a slash-t in the comment. Maybe kbin has different rendering rules for comments?

        • Limitless_screaming@kbin.social
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          11 months ago

          That would be weird if a string containing a space wasn’t equal to 0 " " == 0, but that’s not the case in JS. If you think that "" and " " being equal to 0 is weird then I agree, but since they are, you should expect "\t" and "\n" to equal 0 too.

        • Ephera@lemmy.ml
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          11 months ago

          The == operator in JS will try to cast the things being compared and do all kinds of ‘smart’ assumptions about what equality means. This is why everyone uses === instead…

    • jtk@lemmy.sdf.org
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      11 months ago

      Yeah, it’s true. I knew all the other ones, had to put that one in the dev tools console to believe it. I was just happy to know === continues to be sane in that comparison.

    • Blackmist@feddit.uk
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      11 months ago

      You have to remember that the underlying principle of JavaScript seemed to be “never throw an error”, even if what it’s being told to do is weapons grade bollocks.