Hello everyone, I wonder why the following taken from an stackoverflow answer doesn't work: https://stackoverflow.com/questions/71184922/is-it-possible-to-infer-a-type-.... Code of the answer posted here verbatim: ``` {-# LANGUAGE ImplicitParams #-} {-# LANGUAGE RankNTypes #-} module Temp where withX :: Int -> ((?x :: Int) => r) -> r withX x r = let ?x = x in r somethingThanNeedsX :: (?x :: Int) => Int somethingThanNeedsX = ?x + 2 foo :: Int foo = bar where bar = withX 42 baz baz = somethingThanNeedsX ``` This won't compile with the error message: ``` Orig.hs:19:11: error: • Unbound implicit parameter (?x::Int) arising from a use of ‘somethingThanNeedsX’ • In the expression: somethingThanNeedsX In an equation for ‘baz’: baz = somethingThanNeedsX In an equation for ‘foo’: foo = bar where bar = withX 42 baz baz = somethingThanNeedsX | 19 | baz = somethingThanNeedsX ``` If you give `baz` a type signature which includes the implicit param it compiles. But I think this is a bug. GHC should not require a type signature here. I tried searching for a GHC ticket but I couldn't find one. But that might also be down to me not using the right query. Anyway my question is, is this expected behavior? This really makes implicit params less ergonomic. Best regards, Rowan Goemans