blob: e4aa61426424ceedbc85e0ecc111b3d32bdc60f3 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
T2664.hs:32:52: error:
• Could not deduce (b ~ a) arising from a use of ‘newPChan’
from the context: ((a :*: b) ~ Dual c, c ~ Dual (a :*: b))
bound by the type signature for:
newPChan :: forall c.
((a :*: b) ~ Dual c, c ~ Dual (a :*: b)) =>
IO (PChan (a :*: b), PChan c)
at T2664.hs:24:5-12
‘b’ is a rigid type variable bound by
the instance declaration
at T2664.hs:23:10-52
‘a’ is a rigid type variable bound by
the instance declaration
at T2664.hs:23:10-52
• In the third argument of ‘pchoose’, namely ‘newPChan’
In the first argument of ‘E’, namely ‘(pchoose Right v newPChan)’
In the expression:
E (pchoose Right v newPChan) (pchoose Left v newPChan)
• Relevant bindings include
v :: MVar (Either (PChan a) (PChan b)) (bound at T2664.hs:25:9)
newPChan :: IO (PChan (a :*: b), PChan c) (bound at T2664.hs:24:5)
|
