[Haskell-cafe] EclipseFP (Haskell IDE) 0.9.1 released

[dagit at eecs.oregonstate.edu]

Quoting Thiago Arrais <thiago.arrais at gmail.com>:

> 2006/2/1, Graham Klyne <GK at ninebynine.org>:
> > [I should say that I haven't yet actually tried this software, though I'd
> like
> > to do so when I get some time.]
>
> I really hope you find the time to do so. We would be glad to be
> hearing from you again.

I haven't found time (yet) to look at your new version, but I tried out the
stable version from about a week ago and played with it a bit.  I might as well
tell you what I found then and why I'm unable to use EclipseFP at this time.

> At some point of the wave, the integrated environments appear. They
> come, as the name says, to integrate the previous tools in an easy to
> use and productive environment. Not that the previous tools were hard
> to use or counter-productive, it is just that by integrating them much
> time is saved from the details and the programmer can spend more time
> on the creative and useful things only he can do.

I think it's important to keep this aspect, the ramping up and the integration.
Particularly, I'm against tools that want to do things their way.  I'd much
rather have the tool automate the tools I already have instead of creating a
new mechanism.  For example, I'd rather have the IDE work with my makefiles
than ignore them and use some builtin make system.  I need to be able to
separate from the IDE whenever it becomes cumbersome or when I want to share
the code.

> > So is there a compelling feature in this Eclipse plugin that isn't easily
> > achieved using simpler tools?
>
> When we write an Eclipse plugin, we get a lot of things for free. Just
> to cite one, there is already CVS integration support within every
> Eclipse installation, which includes a very neat diff viewer. Adding
> support for other version control systems isn't very hard. There are
> plugins, for example, for Darcs and Subversion too.

I was trying the Darcs plugin in conjunction with EclipseFP as my first attempt
at using eclispe.  I found that waiting for eclipse to "autobuild" everything
in _darcs was a waste of time and just plain silly.  Hopefully, there is a way
to avoid this excessive building and still use autobuild.  I couldn't find it.

> Another very nice feature of the Eclipse platform is the refactoring
> support. Wouldn't you like to refactor your Haskell code as easily as
> selecting some context-menu item? Not to mention code assistance and
> 'go to declaration support' (click a module/function/whatever
> reference and open its corresponding declaration). This has saved me a
> lot of time when browsing code.

This is the reason I sought out EclipseFP.  I want to automate as much of the
refactoring as I can while making it safe.  But now let me turn to the reasons
I'm not using it anymore.  Some of the reasons have to do with eclipse itself
(I think), some are related to the very nice plugin you have created, and some
are related to the darcs plugin.  Some of my problems may even be fixed in the
announced version, but I haven't had a chance to check.

I wanted to use EclipseFP to help with darcs development.  The first problem I
encountered was that darcs has a makefile which is growing in complexity.  Some
files are compiled with this flag, others with that flag.  I couldn't figure out
how to import the make rules.  I did find a way to set the compilation options,
but they were per project instead of per file as near as I could tell.  I would
a makefile import to be automated and to watch the makefile for changes.  One
direction would be fine for now, but ultimately I would want it to let me
change build settings in Eclipse and have it mirrored in the makefile.  Does
eclipse have a makefile plugin?  I also had a problem with autobuild building
too much as noted above.  I also couldn't figure out a way to ask eclipse to
delegate to make for building.

The next problem I encountered was the parser was not forgiving enough to parse
the darcs source code, as a result everything was colored as a comment.  Every
file that contained "#include", "#define" or similar threw a lexical error.
The code is meant to be run through ghc with the -cpp flag turned on.  Is it
possible to use ghc-api for parsing the code?  I also noticed that when you
click on an error so that eclipse will take you to the place of the error, it
often took me to lines that were perfectly fine, in fact, I think it was often
the wrong file.

The first time I created a "Hello, World" project in win32 eclipseFP gave some
odd errors that I didn't write down.  I haven't seen that error since so I
can't make a bug report, but it was certainly confusing.  It was to the effect
that ghc had crashed while generating the project.  After I got that error, I
stop using eclipse in windows and switched to OSX.

I had some other problems, but don't think they were related enough to list them
here.  In the end, it was a horrible first experience with eclipse and I'm not
looking forward to ever using eclipse again.  On the other hand, I want some
sort of IDE for Haskell to help automate certain things, like refactoring.  I'm
a long time fan of emacs, but the more I use emacs the more I see that it may
never handle certain things well.  For example, using regexp to do syntax
highlighting is quick and easy it's also the source of many of the problems
with using emacs for coding in Haskell.  The indentation is off, block
uncomment is not the inverse of block comment, if you use a string like "{-" it
throws off the highlighting until a matching -} is found and so on.

My advice would be to download the darcs source code and try to use darcs with
EclipseFP. You'll see first hand some things that could use some fix'n :)  And I
think I could stand to use eclipse to test out your changes if you need a
tester, but I doubt I'd have much more time to spare than testing.

> Of course, you need to write the code to tell the platform about your
> language. That's what the EclipseFP team is trying to do.

Yes, and I'm very happy to see someone doing this.  I wish you the best of luck
and when the problems I encountered are fixed I will try eclipse again.

Hopefully my rantings will be helpful to you and not make you lose hope :)  I
really want see you succeed.

Thanks,
Jason