Thus I searched for a way to get this information for functions, which are defined offside (of the main indentation level).
So, what tools do you use to get the inferred type signature of local functions?
i tend to do that by hand: if i write f .. = e where ..defs.. as f .. = rhs where rhs = e .. defs .. i can replace rhs with anything in scope within f, and test or type it in ghci. the trouble, of course, are the other calls to f, which don't like the change in type. so instead i have to take f out of production use, somewhat like this f .. = undefined f' .. = rhs where rhs = e[f'/f] .. defs[f'/f] .. and use f' for testing and typechecking.. so, if you get your alternative to work, i'd be interested to add that to my own vim scripts as well!-) it seems one needs to compile the source before one can use -ddump-tc?
But '-ddump-tc' includes type signatures of offside defined functions.
I.e. something like
ghc -ddump-tc Foo.lhs 2>&1 \ | awk '/^[A-Z].+lhs/, ! // { print $0; }' \ | awk '/ :: / , /\[\]/ { if (!($0 ~ /\[\]/)) print $0; }' \ | less
does the trick.
But as the haskell/ghc wiki mentions, the -ddump-* output is optimized for human reading and not for some kind of 'automatic use'. For automatic use one should look at the GHC-API ...
Well, I mention this, because I would like to integrate some lookup feature (for type signatures) into vim (if it doesn't exist yet).
GHC-API would be the preferred solution, but editor bindings traditionally have to interpret all kinds of output not intended for anyone's consumption. you can certainly store the output, do substitutions, and associate types with identifiers via associative arrays, so you need only one call to get all local types, if you can extract and identify the information. claus