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| author | Joey Hess <joeyh@joeyh.name> | 2018-04-30 09:03:46 -0400 |
|---|---|---|
| committer | Joey Hess <joeyh@joeyh.name> | 2018-04-30 09:03:46 -0400 |
| commit | 14fe4c4d6b5a29be94ecfc0572e0f9a9a081e795 (patch) | |
| tree | 38ad23b09bd21a8569568335a13bfde9c16e79c1 /src/Propellor/Property/Debootstrap.hs | |
| parent | 96ea8e04251bc23dd27faf1f486a2a9f9c29ff98 (diff) | |
fix broken SemigroupMonoid transition <<loop>>
Turns out that with ghc 8.2.2, the instructions given on the page don't
work. And the cppless variant that I had compiles, but into effectively
mappend = mappend so it loops.
The only way I can see to make it work without cpp is to use
mappend = (Sem.<>)
which is ugly and a land mine waiting to explode if someone changes it
to a nicer mappend = (<>) with a newer version of ghc which will compile
it and work ok, while breaking it with 8.2.2. Sigh.
I posted to haskell-cafe about this.
Diffstat (limited to 'src/Propellor/Property/Debootstrap.hs')
| -rw-r--r-- | src/Propellor/Property/Debootstrap.hs | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/Propellor/Property/Debootstrap.hs b/src/Propellor/Property/Debootstrap.hs index c6e5c373..923229be 100644 --- a/src/Propellor/Property/Debootstrap.hs +++ b/src/Propellor/Property/Debootstrap.hs @@ -41,7 +41,7 @@ instance Sem.Semigroup DebootstrapConfig where instance Monoid DebootstrapConfig where mempty = DefaultConfig - mappend = (<>) + mappend = (Sem.<>) toParams :: DebootstrapConfig -> [CommandParam] toParams DefaultConfig = [] |