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0 pointsmumblemumble5y ago0 comments

Clojure is strongly typed. I think you mean statically typed.

They're orthogonal concerns. C is statically and weakly typed. Clojure is dynamically and strongly typed. PHP is dynamically and weakly typed. Haskell is statically and strongly typed. Java, as the most design-by-committe language ever, manages to be a mix of all four.

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jbritton5y ago

Weak typing is when types get automatically transformed like 2 + “3” == 5, “2” + 3 == “23”. Strong typing doesn’t do these types of automatic conversions and throws exceptions or generates a compiler error.

Static typing — types checked at compile time. Dynamic typing — types checked at runtime.

jolux5y ago

"Strong" typing doesn't mean much of anything and I generally try to avoid using it but slipped up here. When I do use it, I use it as a synonym for static languages with expressive type systems. I prefer statically typed languages.

dependenttypes5y ago

Strong typing generally does not mean much and everyone seems to be using a different definition. Would you consider Javascript weakly typed? What about Python?

mumblemumbleOP5y ago

I'd consider JavaScript to be more toward the weak typing end of things, because it does lots of automatic conversions with surprising results. (see, for example, Gary Bernhardt's "Wat?" lightning talk.) I don't think I'd consider it as weak as C, which has things like unions and pointers that let you just sort of fall out of the type system entirely.

I'd consider Python to be more strongly typed than JavaScript. It doesn't do quite so many automatic conversions. For example, in Python, `1 + "foo"` is a TypeError. In JavaScript, it's "1foo". Sadly, `1 == True` in Python, so it certainly doesn't get full marks.

dependenttypes5y ago

What about Haskell then?

    {-# LANGUAGE MultiParamTypeClasses, TypeSynonymInstances, FlexibleInstances #-}

    import Prelude (String, (++), show, Int, (==))
    import qualified Prelude

    class Add x y where
      (+) :: x -> y -> y
    
    instance Add Int String where
      (+) x y = show x ++ y
    
    instance Add Int Int where
      (+) x y = x Prelude.+ y
    
    instance Add String String where
      (+) x y = x ++ y
    
    a = ((1 :: Int) + (1 :: Int)) == 2
    b = ((1 :: Int) + "aa") == "1aa"
    c = ("a" + "aa") == "aaa"

jolux5y ago

Examples like the last one about Python are why I think it’s approximately meaningless as a descriptor. I don’t see why dynamic languages should have any implicit conversions at all.

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jbritton5y ago

Static typing — types checked at compile time. Dynamic typing — types checked at runtime.

jolux5y ago

dependenttypes5y ago

Strong typing generally does not mean much and everyone seems to be using a different definition. Would you consider Javascript weakly typed? What about Python?

mumblemumbleOP5y ago

dependenttypes5y ago

What about Haskell then?

    {-# LANGUAGE MultiParamTypeClasses, TypeSynonymInstances, FlexibleInstances #-}

    import Prelude (String, (++), show, Int, (==))
    import qualified Prelude

    class Add x y where
      (+) :: x -> y -> y
    
    instance Add Int String where
      (+) x y = show x ++ y
    
    instance Add Int Int where
      (+) x y = x Prelude.+ y
    
    instance Add String String where
      (+) x y = x ++ y
    
    a = ((1 :: Int) + (1 :: Int)) == 2
    b = ((1 :: Int) + "aa") == "1aa"
    c = ("a" + "aa") == "aaa"

jolux5y ago

Examples like the last one about Python are why I think it’s approximately meaningless as a descriptor. I don’t see why dynamic languages should have any implicit conversions at all.

1 more reply

j / k navigate · click thread line to collapse