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”.
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.
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.
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.