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0 pointscatnaroek10y ago0 comments

Here is why: http://pastebin.com/t3Q3CW4j

This is particularly infuriating because the proper way to handle bound variables is already known: https://en.wikipedia.org/wiki/De_Bruijn_index .

0 comments

i_s10y ago

No one is maintaining state by constantly clobbering namespace level variables in Clojure, though. What actually comes into play are ways the language and standard library encourages passing data around and manipulating it, which in Clojure is as immutable as you'll find in any language.

catnaroekOP10y ago

Clojure encourages me to program in the REPL, because there is no other way to know what is going on in such a semantically crazy language, other than trial and error.

And the state of the Clojure REPL is as mutable and imperative as it gets, as my paste showed.

greydius10y ago

You can rebind variables in ghci, too. I certainly wouldn't say this is evidence that Haskell promotes mutable data.

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gclaramunt10y ago

Interestingly, Scala handles it http://pastebin.com/CT36K6Hj It feels like an artifact of the REPL tho, as one shouldn't be able to redefine x

catnaroekOP10y ago

Yep, statically typed languages tend to have no option but to handle this right. Otherwise, they risk unsoundness: Consider what would happen if you did `val x = "foo"` instead of `val x = 0`.

But there's still no type-level distinction between immutable and mutable bindings, which is why included Scala in the “anything goes” category.

j / k navigate · click thread line to collapse

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i_s10y ago

catnaroekOP10y ago

Clojure encourages me to program in the REPL, because there is no other way to know what is going on in such a semantically crazy language, other than trial and error.

And the state of the Clojure REPL is as mutable and imperative as it gets, as my paste showed.

greydius10y ago

You can rebind variables in ghci, too. I certainly wouldn't say this is evidence that Haskell promotes mutable data.

1 more reply

gclaramunt10y ago

Interestingly, Scala handles it http://pastebin.com/CT36K6Hj It feels like an artifact of the REPL tho, as one shouldn't be able to redefine x

catnaroekOP10y ago

Yep, statically typed languages tend to have no option but to handle this right. Otherwise, they risk unsoundness: Consider what would happen if you did `val x = "foo"` instead of `val x = 0`.

But there's still no type-level distinction between immutable and mutable bindings, which is why included Scala in the “anything goes” category.

j / k navigate · click thread line to collapse