[commit: ghc] ghc-8.4: Various documentation improvements (a666e43)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-8.4
Link       : http://ghc.haskell.org/trac/ghc/changeset/a666e43200d88a847d751a62c90f502e0c90e9ff/ghc

>---------------------------------------------------------------

commit a666e43200d88a847d751a62c90f502e0c90e9ff
Author: Sergey Vinokurov <serg.foo at gmail.com>
Date:   Wed Feb 7 21:10:17 2018 +0000

    Various documentation improvements
    
     * Fix missing code example in changelog for 8.4.1
    
     * List 'setEnv' as opposite of 'getEnv'
    
       It seems best to direct users to use 'System.Environment.setEnv'
       rather than 'System.Posix.Env.putEnv'. This is due to 'setEnv' being
       located in the same module as 'getEnv' and my virtue of working on
       Windows platform, whereas 'putEnv' does not have that quality because
       it's part of the 'unix' package.
    
     * Reflect in docs the fact that 'readMVar' is not a composition of
       'takeMVVar' and 'putMVar' any more
    
    (cherry picked from commit df449e1744d59eef7f41e09196629bc01815e984)


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a666e43200d88a847d751a62c90f502e0c90e9ff
 libraries/base/Control/Concurrent/MVar.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libraries/base/Control/Concurrent/MVar.hs b/libraries/base/Control/Concurrent/MVar.hs
index 393fca8..fa99361 100644
--- a/libraries/base/Control/Concurrent/MVar.hs
+++ b/libraries/base/Control/Concurrent/MVar.hs
@@ -41,8 +41,8 @@
 -- atomic operations such as reading from multiple variables: use 'STM'
 -- instead.
 --
--- In particular, the "bigger" functions in this module ('readMVar',
--- 'swapMVar', 'withMVar', 'modifyMVar_' and 'modifyMVar') are simply
+-- In particular, the "bigger" functions in this module ('swapMVar',
+-- 'withMVar', 'modifyMVar_' and 'modifyMVar') are simply
 -- the composition of a 'takeMVar' followed by a 'putMVar' with
 -- exception safety.
 -- These only have atomicity guarantees if all other threads