Haskell List Problems

[kh]

Folks,

We've switched to manual moderation of the Glasgow end of the Haskell
list until we've dealt with the US-generated mail failures. There may
be a few failure messages still in the pipeline, so please be patient
with us.

Kevin

Research Assistant Post

[wadler]

  RESEARCH ASSISTANT POST AVAILABLE

`Save Space with Linear Types'
 Philip Wadler, University of Glasgow

A research assistant post is available under the SERC grant, `Save
Space with Linear Types'.  The goals of this project are to:

* Design a linear type system that allows fine control over
space usage.

* Implement this type system by modifying the Glasgow Haskell
compiler.

* Measure the performance of the modified compiler on
suitable benchmarks.

* Seek improved theoretical foundations for linear types.

Preferably, the candidate should be a top-notch functional programmer
who knows a little bit about types, or a top-notch type theorist who is
a competent functional programmer.  Knowledge of Haskell (a non-strict
functional language) is not essential, but the candidate must be
capable of learning Haskell quickly.

The post is for three years beginning in January 1994.  (A change in
the start date may be negotiated.)  The post pays 15,563 UK pounds in
the first year, with an annual increase.  The RA will be equipped with
a Sun workstation, and there are adequate funds for travel.

The Glasgow functional programming group enjoys a strong reputation.
We are headquarters of the Journal of Functional Programming, and hold
an annual functional programming workshop, the proceeds of which are
published by Springer Verlag.  The Computing Science department
provides an excellent and supportive research environment; in the
recent UK research assesment exercise, the department received 5,
the highest possible rating.  The city of Glasgow itself is a very
pleasant place to live, has strong support of theatre and the arts,
and is enticingly close to the Highlands and Islands of Scotland.

To apply, please send a cover letter outlining your qualifications
for the post and a copy of your c.v.  Electronic applications are
encouraged, as are inquiries for further details.  The deadline
for applications is 15 October 1993.

I look forward to working with one of you!  -- P

---
Professor Philip Wadler[EMAIL PROTECTED]
Department of Computing Sciencetel: +44 41 330 4966
University of Glasgow  fax: +44 41 330 4913
Glasgow G12 8QQ, SCOTLAND

haskell

[Aiden McCaughey]

Help !!!

I am interested in the Glasgow Haskell monadic IO system. I have
read 'Imperative Functional Programming' by Peyton Jones and Wadler
and have tried to implement some of the sample functions but with
little success. 

1. Can you shed some light on what I am doing wrong and
2. Point me in the right direction to obtain some more detailed
   documentation on using monadic IO with the Glasgow Haskell compiler
   version 0.16 (if any exists!).

Many thanks,

Aiden McCaughey
Dept Applied Computing
Magee College
University Of Ulster
email: [EMAIL PROTECTED]

P.S My sample program and error messages are listed below

--
-- Script monio.hs
module Main where
import PreludeGlaIO

putcIO :: Char -> IO ()
putcIO c = ccall putchar c

mainIO :: IO ()
mainIO = putcIO '?'
-- end

Compiled as follows:
$ ghc -o test monio.hs -fglasgow-exts
with following error

"monio.hs", line 5
   couldn't match the type "pt4" against "Char"
   when combining a functions equation(s) & type signature (if applicable)
putcIO c = ccall putchar c
Fail: compilation had errors
ghc: execution of Haskell Compiler had trouble

---

The following program compiles but on execution does nothing !

-- Script monio1.hs
module Main where
import PreludeGlaIO

mainIO :: IO ()
mainIO = appendChanIO "stdout" "Hello World"
-- end

---