[Haskell-cafe] Refactoring status

[Peter Verswyvelen]

> Which extensions are you using that are not Haskell 98? I would be very
> interested to know what users would generally require from a refactorer.

I don't see myself as typical Haskell user yet, I'm way to new to the
language to consider myself a real "user". 

Currently, I'm trying to learn arrows and Yampa (mainly to see how well it
compares to my own dataflow/reactive stuff that was written in C#, C++ and
assembler)

I also needed functional dependencies, and usually my code does not compile
without -fglasgow-exts, and I really don't know why :) 

> I agree with Neil, AST editors are generally ugly and hard to use. There
> is also the problem of laying out Haskell code. Everyone uses their own
> layout style and pretty printing ASTs is generally a bad thing to do in
> this context.

First of all, let's see if I get the concept of a "syntax directed editor"
right. The idea is, that I (or my company), has a specific indentation rule,
naming convention rule, etc... When I get code from someone else (in a
syntax tree form ala XML), it will immediately show the text using my
conventions. Furthermore, when I need to perform refactoring, a rename is
just *one* change to the entire system, no matter how many other files use
the name; no more merging for stupid renames. When diffing, whitespace,
indentation, etc does not matter; the structure of the files is compared
instead. A lot of metadata (for different views) can be attached to the
syntax tree without cluttering my text files (like e.g. most version control
systems do). I could go on like that, but the intentional programming
website explains most of it.

Cheers,
Peter