More flexible literate Haskell extensions (Trac #9789), summary on wiki

Sven Panne svenpanne at
Thu Nov 20 10:40:22 UTC 2014

2014-11-20 9:36 GMT+01:00 Joachim Breitner <mail at>:
> [...] With your extensions it will have to read the directory contents. In
> most situations, that should be fine, but it might cause minor
> inconveniences with very large directories, many search paths (-i flags)
> and/or very weird file systems (compiling from a FUSE-mounted
> HTTP-Server that does not support directory listing? Would work now...)

Hmmm, IMHO reading directory contents is not a good idea for a
compiler, for just the reasons you mentioned.

> A fixed set of extensions (e.g. just "md" and "tex") would avoid this
> problem, but goes against the spirit of the proposal.

I think we can get the best of both worlds by adding a compiler flag,
e.g. --literate-extensions=md,tex. This way the compiler still has to
probe only a finite set of filenames *and* we are still flexible.


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