[Haskell-cafe] Possible Improvements

[Don Stewart]

> Fully lazy:
> 
>     data Tree = Leaf Int | Node Tree Int Tree
> 
>     $ time ./A 25
>     49           
>     ./A 25  18.20s user 0.04s system 99% cpu 18.257 total
>                                              ^^^^^^
>     3556K heap use.
> 
> Strict in the elements, lazy in the spine:
> 
>     data Tree = Leaf !Int | Node Tree !Int Tree
> 
>     $ time ./A 25      
>     49
>     ./A 25  14.41s user 0.03s system 99% cpu 14.442 total
>                                              ^^^^^^
>     3056K heap use.

And, oh, element strict, with -funbox-strict-fields,

    $ time ./A 25
    49
    ./A 25  12.25s user 0.01s system 99% cpu 12.346 total

-- Don