On 2012-Jul-07, Henning Thielemann wrote:
On Thu, 5 Jul 2012, gdweber@iue.edu wrote:
Sifflet and sifflet-lib 2.0.0.0, now available on Hackage!
This version introduces a type checker and partial support for higher order functions in Sifflet, the visual, functional programming language and support system for students learning about recursion.
You have implemented your own type-checker, right?
It is my code implementing the type checker from Simon Peyton-Jones's book "The Implementation of Functional Programming Languages" (1987).
I plan to add a type-checker to our live-sequencer project. [1] So far I have thought about using the Helium type checker but I have not done it so far. If you want to make your type-checker useful for other projects, you may put it into a separate package without the hard to install dependencies on cairo and glib.
I am very interested in receiving suggestions for modularizing my packages, and I thank you for this one. I should point out that the Sifflet type checker (unlike Helium's) is not a type checker for Haskell, or even a reduced version of Haskell, but for a very small language consisting of these expressions (from Language.Sifflet.Expr): data Expr = EUndefined | ESymbol Symbol | EBool Bool | EChar Char | ENumber Number | EString String | EIf Expr Expr Expr -- ^ if test branch1 branch2 | EList [Expr] | ELambda Symbol Expr | EApp Expr Expr -- ^ apply function to argument | ECall Symbol [Expr] -- ^ function name, arglist | EOp Operator Expr Expr -- ^ binary operator application | EGroup Expr -- ^ grouping parentheses deriving (Eq, Show) (there are some redundant variants there, because I designed Expr before thinking about type checking and then augmented it to add the type checker) and these types data Type = TypeVar TypeVarName -- named type variable | TypeCons TypeConsName [Type] -- constructed type deriving (Eq) Do you still think my type checker would be useful to you, or to Haskellers generally?
Ah, I enjoyed the performance! Greg -- Gregory D. Weber, Ph. D. : Associate Professor of Informatics / \ Indiana University East 0 : Tel. (765) 973-8420; FAX (765) 973-8550 / \ http://mypage.iu.edu/~gdweber/ 1 []