Strictness annotations on type parameters

Bulat Ziganshin bulatz at
Wed Dec 7 08:05:00 EST 2005

Hello Ralf,

Wednesday, December 07, 2005, 12:43:33 PM, you wrote:

>> It's hard to avoid the feeling that one ought to be able to say
>> something useful about strictness in the types but it's swampy
>> territory, and hard to get right.

RH> Fortunately, it's easy to dry up the `swampy territory'. The type
RH> `Contract' below models strictness requirements. The function
RH> `assert' implements them (`assert c' is a so-called projection).
RH> Feel free to experiment with different designs ...

i don't understand anything in what you wrote :)  but week or two ago
there is a brief discussion in libraries maillist about need of
creating strict and lazy variants of libraries, for example for monads
and data structures (Maps, Trees and so on). can you say something
about automatic generation of strict library from lazy one, or about
generating them both from some template?

Best regards,
 Bulat                            mailto:bulatz at

More information about the Glasgow-haskell-users mailing list