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Comment by danbruc | Hacker News Reader

Being able to make good decisions does not guarantee you will never make a mistake. And he even explains his reasoning behind his choice and it was a justifiable decision when he made it. But I stand by what I said - if you are unable to decide between using 8 bit or 64 bit integers or a floating point type or a decimal type you should not be a professional software developer because it is really a very basic and fundamental skill.

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In the web industry, which is the biggest part of the software industry by people employed, most developers use dynamically typed languages and very happily never make this "fundamental" choice. Should they all resign?

Not only web industry: in Smalltalk every integer can have unlimited number of bits. On 32-bit systems internally 31 bit is used first and with overflow it automatically starts using variable size integers... There is no need to make a choice on the number of bits... Just use integers as they are in the nature...

Dynamically typed does not mean that you don't have to think about number types - 3/2 and 3/2.0 may yield different results in dynamically typed languages.

And how many web developers don't know about or are unable to decide between different number types? JavaScript type coercion is such a mess, how could you get away without thinking about types, even though number types are usually not an issue?

"JavaScript type coercion is such a mess" - in what way? Seriously.

In what way it isn't? Just look at this beauty [1] and its consequences. But probably nobody uses the equality operator anymore because it is such a mess. Less than is even more messed up [2].

[1] http://people.mozilla.org/~jorendorff/es5.html#sec-11.9.3

[2] http://strilanc.com/visualization/2014/03/27/Better-JS-Equal...

`" " == 0 == false`, and `"" == 0 == false`, but `" " != ""`.

`"Infinity" == Infinity`, but `"true" != true`.

I could go on for a while like this.

And which of those persist if you use ===?

None - because === does not coerce types. Type coercion, not double-equal weirdness as such, is the gripe of the GGP. Non-transitive, inconsistent equality is nothing more than a symptom of JS's rules for implicit conversions.

Language-war disclaimer: I love javascript and everything, it's a very expressive language; but a good wodge of the tooling around it nowadays is to help people avoid things like implicit type-coercion 'surprises'.

That is not specifically type coercion, but the behavior of the equality (==) operator in JavaScript. Type coercion in JavaScript can be very useful, for example !!('foo') is coercive and easily understood (and has an unsurprising result). Thankfully the == operator is completely optional and has a more easily understood === (identity) correspondent, making your point less about a language and more about a specific operator within a language.

It is type coercion. The runtime converts both operands to the same type before making the comparison (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...). This is also true of !, <, and friends.

Other operators in JavaScript may behave more intuitively than ==, but I don't think you can really make a good case for JavaScript's type coercion being 'unsurprising'.

I suppose what I meant was that you point out that the coercive behavior of some operators is counter intuitive; ergo type coercion in JS is a mess. I dont think that follows because some operators behave in a coercive fashion more convenient than many other languages.

Well, your first line doesn't make sense, since the first two comparisons are using type coercion but the third isn't, so it's like saying `0 == false` but `0 !== false` how can this be? (" " != "" is the same as " " !== "")

The second line at least uses type coercion, but still you are making the wrong assumptions. true could be coerced to many strings 't', '1', 'true', 'yes', 'on', but they chose to use '1' (You may not like it but I think it's a good choice). Infinity on the other hand has not many choices when coercing it to a string I can think of '∞' (which is difficult to type), 'Infinity', and maybe 'Inf.' so I think they made a good choice here.

I'm not saying type coercion in js has no problems, but you said that it's a mess and I just think you chose the wrong examples.

Thankfully Python fixed that discrepancy about 3/2

Anyhow, I don't agree with you: I think that getting a bug years down the road due to a too small numeric type is something that the programming language itself should avoid.... not because "developers don't ought to know it", but because mistakes happen

Anyhow, even with a dynamically typed programming language like Python or Javascript you can care about the size of your numbers.

Just import the array module (in Python) or use the Int32Array/Int8Array/etc. types (in Javascript)

Then what do you propose we call the people who write Ruby, Python, Javascript, PHP, etc. code for a living? Have you heard of accidental complexity?

Ruby, Python and PHP all support several types of numbers. But even if they did not this would not preclude people developing in those languages from being able of making such decisions.

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