[GHC] #5073: Add blockST for nested ST scopes

[GHC]

#5073: Add blockST for nested ST scopes
-------------------------------------+-------------------------------------
              Reporter:  simonpj     |            Owner:
                  Type:  feature     |           Status:  new
  request                            |        Milestone:  7.10.1
              Priority:  low         |          Version:  7.0.3
             Component:  Compiler    |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:              |  Related Tickets:
  None/Unknown                       |
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------
Changes (by thomie):

 * difficulty:   => Unknown
 * type:  bug => feature request


--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5073#comment:10>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler