2011/10/18 Roel van Dijk
Maybe we [can] create an example program which would fail with the more general type.
Migrating the function "foo" from bytestring to vector-bytestring would fail with more general types:
import Data.ByteString foo = print empty Ok, modules loaded: Test.
With vector:
import Data.Vector.Storable foo = print empty Ambiguous type variable `a0' in the constraints: (Show a0) arising from a use of `print' at /home/roelvandijk/development/test.hs:5:7-11 (Storable a0) arising from a use of `empty' at /home/roelvandijk/development/test.hs:5:13-17 Probable fix: add a type signature that fixes these type variable(s) In the expression: print empty In an equation for `foo': foo = print empty Failed, modules loaded: none.