Move `Plugin` and `PluginAction` to a new module

Move our base plugin types to a new module to enable us to use them in
both the plugin matching code (which we'll leave in "Plugin.hs") and in
specialised plugin modules.

This enables us to import and provide a list of plugins in `plugins` in
"Plugin.hs" and use these types in that file and in the plugin files
without any circular/recursive module dependencies.

3 files changed, 20 insertions, 11 deletions

diff --git a/sorbot.cabal b/sorbot.cabal
index 49c21fa..a581bea 100644
--- a/sorbot.cabal
+++ b/sorbot.cabal
@@ -17,6 +17,7 @@ library
   hs-source-dirs:      src
   exposed-modules:     Lib
                      , Plugin
+                     , Plugin.Base
   build-depends:       base >= 4.7 && < 5
                      , regex-tdfa
   default-language:    Haskell2010
diff --git a/src/Plugin.hs b/src/Plugin.hs
index 6522e0b..41b0296 100644
--- a/src/Plugin.hs
+++ b/src/Plugin.hs
@@ -1,21 +1,12 @@
 module Plugin
-    ( Plugin
-    , matchPlugin
+    ( matchPlugin
     , performPlugin
     , plugins
     ) where
 
 import Text.Regex.TDFA
 
-type PluginAction = String -> String
-
-data Plugin = Plugin
-    { matchRegex :: String
-    , perform    :: PluginAction
-    }
-
-instance Show Plugin where
-    show (Plugin r p) = "matchRegex = " ++ r
+import Plugin.Base
 
 matchPlugin :: String -> Maybe Plugin
 matchPlugin message = firstPlugin $ matchPlugins message plugins
diff --git a/src/Plugin/Base.hs b/src/Plugin/Base.hs
new file mode 100644
index 0000000..c73ef6a
--- /dev/null
+++ b/src/Plugin/Base.hs
@@ -0,0 +1,17 @@
+module Plugin.Base
+    ( PluginAction
+
+    , Plugin(..)
+    , matchRegex
+    , perform
+    ) where
+
+type PluginAction = String -> String
+
+data Plugin = Plugin
+    { matchRegex :: String
+    , perform    :: PluginAction
+    }
+
+instance Show Plugin where
+    show (Plugin r p) = "matchRegex = " ++ r