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unintuitive error message about unbalanced parentheses

A minimal test case is as follows:

testFunc file = do

let file1 = file) return file1

If you try to load it, you will get:

  1. ..\test.hs:111:2:

The last statement in a 'do' construct must be an expression

This error message is kind of unfriendly, and probably only GHC authors know how a mismatched parenthesis can lead to such an error message.

Trac metadata
Trac field Value
Version 6.10.3
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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