diff options
Diffstat (limited to 'compiler/simplCore/CallArity.hs')
| -rw-r--r-- | compiler/simplCore/CallArity.hs | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/compiler/simplCore/CallArity.hs b/compiler/simplCore/CallArity.hs index bead230bcd..5ee5fe296a 100644 --- a/compiler/simplCore/CallArity.hs +++ b/compiler/simplCore/CallArity.hs @@ -33,7 +33,7 @@ Note [Call Arity: The goal] ~~~~~~~~~~~~~~~~~~~~~~~~~~~ The goal of this analysis is to find out if we can eta-expand a local function, -based on how it is being called. The motivating example is code this this, +based on how it is being called. The motivating example is this code, which comes up when we implement foldl using foldr, and do list fusion: let go = \x -> let d = case ... of @@ -46,7 +46,7 @@ If we do not eta-expand `go` to have arity 2, we are going to allocate a lot of partial function applications, which would be bad. The function `go` has a type of arity two, but only one lambda is manifest. -Further more, an analysis that only looks at the RHS of go cannot be sufficient +Furthermore, an analysis that only looks at the RHS of go cannot be sufficient to eta-expand go: If `go` is ever called with one argument (and the result used multiple times), we would be doing the work in `...` multiple times. |