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What is broken about for in? A quick search didn't turn up anything for me. I don't write much Javascript but for the times I do this seems like it could be use

• layer8 4y ago
  You need to up your Google-foo. E.g.: https://stackoverflow.com/questions/500504/why-is-using-for-in-for-array-iteration-a-bad-idea https://stackoverflow.com/questions/500504/why-is-using-for-...
  • pavlov 4y ago
    That talks about using for…in with arrays, but not plain objects. IMO it’s fine for iterating over object keys. Sure, there are bizarre ways to make your objects go nuts in JavaScript through prototypal inheritance, but if you’re doing that then for…in is not your biggest problem.
    • IshKebab 4y ago
      You shouldn't normally need to iterate over object keys. Doing so is a pretty big indication of bad design. If you do you should use `Object.entries()` which avoids enumerating properties in the prototype chain. There's really no reason at all to use for-in and its use is usually a mistake.
      • pavlov 4y ago
        This is weird advice IMHO. It seems like you’re saying that iterating over dictionary keys is bad in general, not just in JavaScript. Doesn’t make any sense to me.
        • IshKebab 4y ago
          I'm not at all. If you want a map you should use `Map`. You generally shouldn't use `Object` as a map.