Weakly Typed Haskell - FP Complete

I was recently doing a minor cleanup of a Haskell codebase. I started off with some code that looked like this: runConduitRes $ sourceFile fp .| someConsumer This code uses Conduit to stream the contents of a file into a consumer function, and ResourceT to ensure that the code is exception safe (the file is closed regardless of exceptions). For various reasons (not relevant to our discussion now),