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Elixir is dynamically typed, just like Erlang and the BEAM. Strong typing is a most requested feature from outside the community, seldom from inside. (EDIT co

Elixir is dynamically typed, just like Erlang and the BEAM. Strong typing is a most requested feature from outside the community, seldom from inside. (EDIT correct, strong typing is not static typing. Does anyone make weakly typed languages anymore?)

nemothekid 8y ago
According to wikipedia, Erlang/Elixir is strongly typed. I guess you and the other poster mean static typing?
- Thaxll 8y ago
  https://elixir-lang.org/getting-started/typespecs-and-behaviours.html https://elixir-lang.org/getting-started/typespecs-and-behavi... Elixir is a dynamically typed language, so all types in Elixir are inferred by the runtime.
dudul 8y ago
You may be confusing strongly and statically typed.
rpeden 8y ago
There's no reason a language can't be both strongly and dynamically typed (like Elixir or Python) or statically and weakly typed (like C). :)
Jtsummers 8y ago
Strongly typed meaning that Elixir/Erlang don't allow: 1 + "some string" + [A,List,Of,Somethings] Compared to javascript where: 1 + "2" == "12" Statically typed means that variables and functions hold or return specific types which can be determined before execution.
- gamache 8y ago
  Type coercion does not equal weak typing -- I submit JS and Perl as examples where types are strong but there is a coercion protocol dependent on which types an operator expects around it.
  - Jtsummers 8y ago
    Fair, C may have been a better example. Where nearly everything is actually just a block of bytes of various lengths and can be intermingled fairly freely with minimal effort to get anything past the compiler. Sometimes useful, but the type system ends up offering few meaningful protections as a consequence.
    - firebacon 8y ago
      The types of values and legal conversions between them are well defined in C -- the assumption that everything is just a block of bytes and hence may be casted freely between types is explicitly incorrect (and is what may lead to bad/invalid C code). However, C does allow you to write code that can not proven to be legal with respect to the formal system of the language and get it to compile, I think that is what you are referring to. But just because you can write an invalid program does not mean the type system doesn't exist or is flawed. I can also write an invalid Haskell program. The difference between these two would be that the haskell program can be proven to contain only operations that map to well-defined operations in the formal language model by an automated process, while the same can not be done for C in the general case. However, just because you can not always prove conformance to a formal model using automated means, doesn't mean that no formal model exists (because it does!).
  - firebacon 8y ago
    If we are being pedantic, what is going on here is not type coercion. If it were type coercion, we would expect the add function to have either of these two behaviours: - coerce the input arguments to strings, i.e. implicitly accept two strings and return another string - coerce the input arguments to integers, i.e. implicitly accept two integers and return an integer However, that is not what is happening here. Of course, in Javascript it is implemented as a function that takes the theoretical "Any" type and decides what do do at runtime. But in a statically type language, the equivalent mechanism would be dynamic/multiple dispatch (or a static overload, possibly in combination with a generic/template method) -- not type coercion.
- firebacon 8y ago
  The result add(1: Int, "2": String) -> "12": String can be achieved in any language, regardless of how strict the type system is. All your example shows is that in elxir no such `add(int, string)` operation is provided as part of the standard library/environment, while in javascript, it is. The "+" (operator) case is only special in languages that do not implement operator overloading -- it is completely orthogonal to the type system.
firebacon 8y ago
> Does anyone make weakly typed languages anymore? I don't think anybody ever did. The definition of "strong" and "weak" seem to be entirely subjective; and of course everybody considers their favourite language to be "strongly typed". It's like a reverse no-true-scotsman.

nemothekid 8y ago

According to wikipedia, Erlang/Elixir is strongly typed. I guess you and the other poster mean static typing?

Thaxll 8y ago
https://elixir-lang.org/getting-started/typespecs-and-behaviours.html https://elixir-lang.org/getting-started/typespecs-and-behavi... Elixir is a dynamically typed language, so all types in Elixir are inferred by the runtime.

dudul 8y ago

You may be confusing strongly and statically typed.

rpeden 8y ago

There's no reason a language can't be both strongly and dynamically typed (like Elixir or Python) or statically and weakly typed (like C). :)

Jtsummers 8y ago

Strongly typed meaning that Elixir/Erlang don't allow: 1 + "some string" + [A,List,Of,Somethings] Compared to javascript where: 1 + "2" == "12" Statically typed means that variables and functions hold or return specific types which can be determined before execution.

gamache 8y ago
Type coercion does not equal weak typing -- I submit JS and Perl as examples where types are strong but there is a coercion protocol dependent on which types an operator expects around it.
- Jtsummers 8y ago
  Fair, C may have been a better example. Where nearly everything is actually just a block of bytes of various lengths and can be intermingled fairly freely with minimal effort to get anything past the compiler. Sometimes useful, but the type system ends up offering few meaningful protections as a consequence.
  - firebacon 8y ago
    The types of values and legal conversions between them are well defined in C -- the assumption that everything is just a block of bytes and hence may be casted freely between types is explicitly incorrect (and is what may lead to bad/invalid C code). However, C does allow you to write code that can not proven to be legal with respect to the formal system of the language and get it to compile, I think that is what you are referring to. But just because you can write an invalid program does not mean the type system doesn't exist or is flawed. I can also write an invalid Haskell program. The difference between these two would be that the haskell program can be proven to contain only operations that map to well-defined operations in the formal language model by an automated process, while the same can not be done for C in the general case. However, just because you can not always prove conformance to a formal model using automated means, doesn't mean that no formal model exists (because it does!).
- firebacon 8y ago
  If we are being pedantic, what is going on here is not type coercion. If it were type coercion, we would expect the add function to have either of these two behaviours: - coerce the input arguments to strings, i.e. implicitly accept two strings and return another string - coerce the input arguments to integers, i.e. implicitly accept two integers and return an integer However, that is not what is happening here. Of course, in Javascript it is implemented as a function that takes the theoretical "Any" type and decides what do do at runtime. But in a statically type language, the equivalent mechanism would be dynamic/multiple dispatch (or a static overload, possibly in combination with a generic/template method) -- not type coercion.
firebacon 8y ago
The result add(1: Int, "2": String) -> "12": String can be achieved in any language, regardless of how strict the type system is. All your example shows is that in elxir no such `add(int, string)` operation is provided as part of the standard library/environment, while in javascript, it is. The "+" (operator) case is only special in languages that do not implement operator overloading -- it is completely orthogonal to the type system.

firebacon 8y ago

> Does anyone make weakly typed languages anymore? I don't think anybody ever did. The definition of "strong" and "weak" seem to be entirely subjective; and of course everybody considers their favourite language to be "strongly typed". It's like a reverse no-true-scotsman.