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Comment by sodapopcan | Hacker News Reader

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.

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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.

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