Re: [Haskell-cafe] Hierarchical modules issue

2010/7/19 Ivan Miljenovic :

On 19 July 2010 14:31, Jonathan Geddes wrote:

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Now when I'm working in a subdirectory, say Foo where the modules are named Foo.Bar, Foo.Baz, Foo.etc., and I try to compile Bar.hs which imports Foo.Baz, the compiler looks for the file Foo/Baz.hs. The problem is that I'm already in the directory Foo and so the compiler fails to find the file for the module Foo.Baz. If I compile the whole project from the root project directory where the main file is, the compiler finds every module just fine.

A similar query was just asked: http://www.haskell.org/pipermail/haskell-cafe/2010-July/080523.html

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It seams very strange to me that when the compiler is compiling a module named Foo.Bar and there is an import for Foo.Baz, the compiler doesn't look in the directory where Foo.Bar is located (the current dir)!

Run ghc[i] from the root (source) directory of your project, not within the hierarchy (note that haskell-mode for emacs tries to do this by finding where the .cabal file is, etc.).

Alternatively, you can fire ghci with the -i option, e.g. ghci -i.. to look at the directory above (not there is no space between the -i and the ..). I do this to run tests which are located in a subdirectory. Otherwise I follow Ivan's advice of running from the root (which makes it easy to open any other file: sub-module, README, or .cabal). Cheers, Thu