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Comment by shijie | Hacker News Reader

The language is still strongly typed, and with the language being purely functional, I found myself not missing static typing nearly as much as I thought I would. Things just work, and they break during compilation if they don’t.

I will say that editor support for static languages is categorically better due to the language server being able to more completely reason about the state of your code. That’s the one drawback.

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> Things just work, and they break during compilation if they don’t.

You omitted the caveat: the program will behave in unexpected ways sometimes. What else do you do to ensure correctness?

ie The minimum bar for modern software is not "it compiles, ship it".

Elixir is not strongly typed. You can bind any data type to a variable at any time.

Parent is making a distinction between “strongly” and “statically” typed. By some definitions. Type conversions in Elixir are generally explicit (contrast with JavaScript) and the type of a variable matters at runtime (e.g think about pattern matching), and so some people would call it “dynamic and strongly typed”.

Elixir doesn't technically have variables. Those are bindings: you give names to values. Variable would be more like a box storing a value.

You're thinking of statically typed, which Elixir isn't. Elixir is strongly typed, which means something different.

This is not true.

For example doing "1" + 2 would give you an error.

You also can't do "foo" + "bar" to get "foobar", you have to do "foo" <> "bar" giving it even more type "strength" than many strongly typed dynamic languages have.

But on the flip side you can also do "if my_var", which will evaluate to true for any non-nil value and non-false value

Is that a common source of typing errors? Genuinely wondering as I don't have a whole lot of experience with statically typed languages. I've personally never had a bug related to it.

I wasn't meaning to imply everything is perfect, though. For example equality operators take anything. I believe there may be changes coming around there.

Do you know if that was a conscious decision for that reason? I always wondered why that operator was used instead of a + sign.

I think it is pretty standard in functional languages not to overload operators. There may be technical reasons as well, I'm a bit out of my depth here, but it probably is better for performance with pattern matching knowing the type? Like `"hello " <> there = "hello there"`. Of course it's not just strings—concatenating lists uses ++ and for dates have their own functions.

OCaml takes it a step further with numbers where `+` only works on integers. You need to do `+.` to add floats. This lets it be statically typed without having to actually specify any types.

Again, a little out of my depth in terms of rock solid explanations.

Elixir is strongly typed, elixir is not statically typed

This is untrue.

https://thinkingelixir.com/elixir-in-the-type-system-quadran....

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