On 29 October 2013 22:36, martin
is there a way to determine types of symbols which are not toplevel but inside a function?
Not at present without transformation. There are two reasonably reliable approaches: Insert noisy holes/make intentional type errors: http://ghc.haskell.org/trac/ghc/wiki/Holes#Insertingdeliberatetypeerrors Implicit parameters: http://ghc.haskell.org/trac/ghc/wiki/Holes#Implicitparameters Holes will land in GHC to support this explicitly. I don't know what version of GHC has/will have this. Alternatively, you can use ghc-mod (https://github.com/kazu-yamamoto/ghc-mod) which, if you can get it to work, can tell you the types of sub-expressions. Lastly, the next version of the FP Complete IDE gives you types of sub-expressions just by clicking on them or selecting them out of the box.