[GHC] #15826: Allow registering (Source)Plugins through the GHC API

[GHC]

#15826: Allow registering (Source)Plugins through the GHC API
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        Reporter:  DanielG           |                Owner:  DanielG
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHC API           |              Version:  8.7
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  D5278
       Wiki Page:                    |
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Comment (by bgamari):

 Alright, I see the use-case here and it sounds reasonable. However, I
 agree that we need to make sure that recompilation checking works in a
 safe and predictable manner. Let's first try to specify what semantics we
 are looking for.

 Here is my guess:

  a. within a GHC session with a `LoadedPlugin` the plugin-module hash
 check should never trigger a recompilation but the plugin's
 `PluginRecompile` strategy should, of course, be able to trigger a rebuild
  b. build artifacts produced by a GHC session with a `LoadedPlugin` should
 never be used by another session

 Does this sound right, DanielG?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15826#comment:8>
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