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"And the custom types are not actually complex, unlike what Clojure leads you to believe with its preference to using the basic built-in types" Custom data typ

"And the custom types are not actually complex, unlike what Clojure leads you to believe with its preference to using the basic built-in types" Custom data types are not always complex, but efficient and useful data types often are. Clojure's data structures have very good performance for immutable data structures. Clojure's maps, for instance, have what effectively amounts to a O(1) lookup, while Haskell's Data.Map is a size balanced binary tree with only O(log n) performance.

dons 14y ago
> effectively amounts to a O(1) lookup So O(log n) then. We obey gravity around these parts. I presume you are referring to HAMT-like structures ,such as found in http://hackage.haskell.org/packages/archive/unordered-containers/0.2.3.0/doc/html/Data-HashMap-Strict.html http://hackage.haskell.org/packages/archive/unordered-contai... which are by no means unique to Clojure. Besides simply having the data type, you still need a good allocator and GC optimized for immutable data, which is where GHC stands alone - http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?test=all&lang=clojure&lang2=ghc http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?t...
- weavejester 14y ago
  > So O(log n) then. We obey gravity around these parts. Which is of no practical difference to O(1) if log n is always very small. > I presume you are referring to HAMT-like structures... which are by no means unique to Clojure. Of course they're not. My point was that it is not trivial to derive a efficient and useful data structure like a HAMT from Haskell's type system. The data structures in a library like unordered-containers are in practise just as opaque to the developer as the core data structures in Clojure.
  - dons 14y ago
    > as opaque to the developer http://hackage.haskell.org/packages/archive/unordered-containers/0.2.3.0/doc/html/src/Data-HashMap-Base.html#HashMap http://hackage.haskell.org/packages/archive/unordered-contai... This highly optimized data type is defined in 6 lines, easily accessible from the docs.
    - weavejester 14y ago
      No it isn't, at least not in any meaningful way. The type definition itself may be 6 lines, but that doesn't adequately describe the data structure, otherwise there'd be no need for the rest of the library.
- lukev 14y ago
  Actually most Clojure maps are Hashtables, which do have O(1) amortized lookup and insert. Granted, the 'amortized' is important.

dons 14y ago

> effectively amounts to a O(1) lookup So O(log n) then. We obey gravity around these parts. I presume you are referring to HAMT-like structures ,such as found in http://hackage.haskell.org/packages/archive/unordered-containers/0.2.3.0/doc/html/Data-HashMap-Strict.html http://hackage.haskell.org/packages/archive/unordered-contai... which are by no means unique to Clojure. Besides simply having the data type, you still need a good allocator and GC optimized for immutable data, which is where GHC stands alone - http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?test=all&lang=clojure&lang2=ghc http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?t...

weavejester 14y ago
> So O(log n) then. We obey gravity around these parts. Which is of no practical difference to O(1) if log n is always very small. > I presume you are referring to HAMT-like structures... which are by no means unique to Clojure. Of course they're not. My point was that it is not trivial to derive a efficient and useful data structure like a HAMT from Haskell's type system. The data structures in a library like unordered-containers are in practise just as opaque to the developer as the core data structures in Clojure.
- dons 14y ago
  > as opaque to the developer http://hackage.haskell.org/packages/archive/unordered-containers/0.2.3.0/doc/html/src/Data-HashMap-Base.html#HashMap http://hackage.haskell.org/packages/archive/unordered-contai... This highly optimized data type is defined in 6 lines, easily accessible from the docs.
  - weavejester 14y ago
    No it isn't, at least not in any meaningful way. The type definition itself may be 6 lines, but that doesn't adequately describe the data structure, otherwise there'd be no need for the rest of the library.
lukev 14y ago
Actually most Clojure maps are Hashtables, which do have O(1) amortized lookup and insert. Granted, the 'amortized' is important.