• Wrench@lemmy.world
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            2 年前

            No one checks those values explicitly.

            if (str) checks if it’s not null, undefined, or empty string.

            Optional chaining like if (arr?.length) checks if list is undefined, null, or empty array.

            Falsy and truthy comparators seem fucky in the beginning when coming from a strongly typed language. But they’re very convenient when used properly.

            • Randelung@lemmy.world
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              2 年前

              Monads exist, optional chaining has been around for ages, and implicit bool casts, too.

              As you said, no one checks those values explicitly.