[Haskell] Re: [Haskell-cafe] Why functional programming matters

Isaac Dupree isaacdupree at charter.net
Sat Jan 26 21:38:36 EST 2008


Derek Elkins wrote:
> On Sat, 2008-01-26 at 20:49 -0500, Isaac Dupree wrote:
>> Michael Reid wrote:
>>> The 
>>> power of Haskell's type system makes it feel like you are programming in 
>>> a dynamic language to some degree, yet all of it is type-checked, and 
>>> that is just *really* cool.
>> to some degree, (in current Haskell compilers), it *is* more like a 
>> dynamic than a static language: except when optimized away, values of 
>> all types are represented by a pointer to their actual value. (this 
>> helps with parametric polymorphism and laziness (take :: Int -> [a] -> 
>> [a]).) (at least this is a difference compared to C++)
> 
> Boxing is orthogonal to dynamic/static.  You can have boxing in
> statically typed languages, e.g. Haskell, Java, C#

yes I know, although we are talking about communicating to people who 
don't necessarily know as much as we do.

> and you can have
> unboxed values in dynamically typed languages.

really? Sure that's possible as an optimization, but I thought that to 
explicitly specify that would require a known static type.  Or perhaps 
the bit-"tagging" by which some Scheme implementations are able to hold 
small integers without a pointer (IIRC)?

~Isaac


More information about the Haskell-Cafe mailing list