testsuite/tests/typecheck/should_fail/tcfail128.stderr


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22


tcfail128.hs:18:16: error:
    Ambiguous type variable ‘b0’ arising from a use of ‘thaw’
    prevents the constraint ‘(Data.Array.Base.MArray
                                b0 FlatVector IO)’ from being solved.
    Probable fix: use a type annotation to specify what ‘b0’ should be.
    These potential instance exist:
      instance Data.Array.Base.MArray IOArray e IO
        -- Defined in ‘Data.Array.Base’
    In a stmt of a 'do' block: v <- thaw tmp
    In the expression:
      do { let sL = ...
               dim = length sL
               ....;
           v <- thaw tmp;
           return () }
    In an equation for ‘main’:
        main
          = do { let sL = ...
                     ....;
                 v <- thaw tmp;
                 return () }