Re: implementation of file-related modules

Jan-Willem Maessen writes:

Alastair Reid writes:

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Following Java's lead and using configuration files to localize a system would potentially allow us to ship portable bytecode files around from one platform to another.

Actually, just delaying binding to System.Directory.Native would be enough (and I bet in such a system we'd want to delay binding to the prelude).

So how would this work? Some #ifdef sections in the implementations that bind System.Directory.Native, depending on which platform we're on? Would this be very hard? Are there more complex issues that I'm not seeing?

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A general mechanism for accessing configuration strings would be useful.

Anyone taking up this task would get to choose a format. A chance to foist your aesthetics on the community! Surely that's irresistable to *somebody*.

I like the idea of type safety, but the configuration strings are probably still useful for some things. How might this look? - A constant CONFDIR (#ifdef'd into the implementations) telling where to find configuration files (a kind of bootstrapping) - A configuration file in CONFIGDIR with (var, val) tuples - The runtime system reads this file at startup? The virtue of this is that there is less work for the haskell implementors if there's just one #ifdef and everything else comes in as strings. Reading the file at runtime, however, seems a little strange since lots of the stuff we're talking about is actually known when you build the compiler. OTOH, maybe the work of having #ifdefs in the implementations isn't that hard? Obviously, there's platform-dependent configuration going on, but is there any going on that is eventually made available as constants or functions? Is there an implementation-neutral way to implement this? peace, isaac