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Comment by pjc50 | Hacker News Reader

This is what happens when people try do to arithmetic in a typeless language. Javascript does not really have a number type; it just has values. Sometimes it infers that you want to do arithmetic on them.

What is the correct order of the items ["2", 10, "banana", [[]], "", 1]?

Bonus: sometimes you can get the same kind of behaviour in Excel when importing CSV.

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The language isn't typeless. Other language (python and ruby, among many others) manage to integer and string comparision correct.

It is trickier when someone compares "2" and 3, should we say it's invalid (my preference) or turn 2 into an integer, or 3 into a string? However, there is NO reason for there to be an issue comparing 1 and 11. This is just an unfortunately mistake that is too deeply baked into the language to fix at this point.

Where is the issue comparing 1 and 11? 1 < 11 still returns true. [11,1].sort((a,b) => a -b) still returns [1, 11].

Sorry, 1 and 11 isn't a problem in javascript. Insert two troublesome numbers :)

Seems like it should be up to you to come up with the troublesome numbers, since you're the one making claims.

Oh sorry, here we go.

    > [2] < [11]
    false

Technically, a combination of integers and arrays. Still took me an afternoon to track down (it didn't occur to me javascript would work like that).

Then your knowledge of Javascript is sorely lacking. To make arrays work like that in Javascript would be very complicated, and counterintuitive to those who know how Javascript arrays work.

I agree my knowledge of JavaScript is lacking, I just (wrongly) assumed arrays would act similarly to other languages.

Obviously it's too late to change JavaScript now, but Iwould be interested to know why it would have been complicated to do this differently originally, and why it would be countintuitive? Is there anything I can read about this kind of thing?

Yeah, that's more or less what you get when you hack a language together in 10 days... Arrays in JS are just a special case of objects, which are just name-value hashmaps. Although they usually have some optimizations in their internal implementation.

I guess "Javascript: the Good Parts" is as good a place to start as any. It doesn't really go into the design decisions though.

It's not that it sometimes infers what you want to do. It's that it has defaults and if you want to do something besides the default, you need to specify what it is you want to do.

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