No look, I don't have /any/ .hi files. I don't know what a .hi file is. I don't have GHC either, I've never managed to make it compile. I just got my very first Haskell compiler (literally 10min ago).

Cheers, Daniel.

Just out of curiosity, what platform are you on? There seem to be builds of GHC available for most common ones. Compiling GHC when binaries are available and you're not intent on changing anything really isn't worth the trouble. (Especially so if you don't already have a previous version of GHC to compile it with). - Cale

David Menendez wrote:

*.hi files are analogous to C's *.h files, except that the compiler generates them.

Thanks, I learned something new today.

You mentioned later that you don't have any *.hi files, so I'm guessing you didn't compile RC4.hs before you compiled prng.hs.

Correct. I didn't know I had to :-)

If I'm right, you need to do something like this first:

$ nhc98 -c RC4.hs

Okay, I did that and I see a .hi file now. Thanks!

Once that step is done, you should be able to compile prng.hs.

Interestingly, I get a different error now: $ nhc98 prng.hs -o prng Undefined first referenced symbol in file FN_RC4_46rand ./prng.o ld: fatal: Symbol referencing errors. No output written to prng collect2: ld returned 1 exit status Oh well, I'll figure this out later. For now I'll just have everything in one big file. At least that compiles cleanly.

Incidentally, if you aren't already familiar with "make" or some other build system, I strongly recommend looking into one. Even for a project with only two files, having a build system keep track of compilation dependencies makes things a lot less tedious.

Ok. I played with make once upon a time. Thanks for the advice. Cheers, Daniel.

David Menendez wrote:

I haven't used NHC so I can't guarantee this will work, but try doing something like this:

$ nhc98 -c RC4.hs $ nhc98 -c prng.hs $ nhc98 RC4.o prng.o -o prng

Yay! It does. And I just put it in a makefile: ------- COMPILER=nhc98 RC4.o: $(COMPILER) -c RC4.hs prng.o: $(COMPILER) -c prng.hs prng: RC4.o prng.o $(COMPILER) RC4.o prng.o -o prng ------- So now I just type 'make prng'. Very nice. Thanks! Cheers, Daniel.

Daniel Carrera wrote:

...

I haven't used NHC so I can't guarantee this will work, but try doing something like this:

$ nhc98 -c RC4.hs $ nhc98 -c prng.hs $ nhc98 RC4.o prng.o -o prng

Yay! It does. And I just put it in a makefile:

------- COMPILER=nhc98

RC4.o: $(COMPILER) -c RC4.hs

prng.o: $(COMPILER) -c prng.hs

prng: RC4.o prng.o $(COMPILER) RC4.o prng.o -o prng -------

This can fail with a parallel make, which may try to compile RC4.hs and prng.hs concurrently. It can also fail if you rebuild after modifying any of the files, as it won't realise that it needs to re-compile. To handle that, you need to be more precise about the dependencies, i.e.: RC4.o RC4.hi: RC4.hs $(HC) -c RC4.hs prng.o prng.hi: prng.hs RC4.hi $(HC) -c prng.hs prng: RC4.o prng.o $(HC) RC4.o prng.o -o prng With most make programs (e.g. GNU make), you can use pattern rules to avoid repeating the commands, e.g.: # how to compile any .hs file to produce .o and .hi files %.o %.hi: %.hs $(HC) -c $< # how to build the prng program prng: RC4.o prng.o $(HC) -o $@ $+ # note that prng.o depends upon RC4.hi prng.o: RC4.hi -- Glynn Clements