blob: 94858c1945acab29d01d20fb427aab5c0bdc7629 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
MonadFailWarnings.hs:19:5: warning:
Could not deduce (MonadFail m)
arising from the failable pattern ‘Just x’
(this will become an error a future GHC release)
from the context: Monad m
bound by the type signature for:
general :: Monad m => m a
at MonadFailWarnings.hs:17:12-25
Possible fix:
add (MonadFail m) to the context of
the type signature for:
general :: Monad m => m a
In a stmt of a 'do' block: Just x <- undefined
In the expression:
do { Just x <- undefined;
undefined }
In an equation for ‘general’:
general
= do { Just x <- undefined;
undefined }
MonadFailWarnings.hs:35:5: warning:
No instance for (MonadFail Identity)
arising from the failable pattern ‘Just x’
(this will become an error a future GHC release)
In a stmt of a 'do' block: Just x <- undefined
In the expression:
do { Just x <- undefined;
undefined }
In an equation for ‘identity’:
identity
= do { Just x <- undefined;
undefined }
MonadFailWarnings.hs:51:5: warning:
No instance for (MonadFail (ST s))
arising from the failable pattern ‘Just x’
(this will become an error a future GHC release)
In a stmt of a 'do' block: Just x <- undefined
In the expression:
do { Just x <- undefined;
undefined }
In an equation for ‘st’:
st
= do { Just x <- undefined;
undefined }
MonadFailWarnings.hs:59:5: warning:
No instance for (MonadFail ((->) r))
arising from the failable pattern ‘Just x’
(this will become an error a future GHC release)
In a stmt of a 'do' block: Just x <- undefined
In the expression:
do { Just x <- undefined;
undefined }
In an equation for ‘reader’:
reader
= do { Just x <- undefined;
undefined }
|
