Add more docs.

Author: qnikst

lazy-cache.cabal

@@ -29,13 +29,20 @@ description:         The library provides an interface for caching the results o
                        6. outdated values are cleared only on accesses to the cache, so if no action is called
                           the data will not be cleared.
                      .
+                     The main entry point of the library is "System.Cache" module, it explains how to
+                     use the library and provides the public API, that does not depend on the actual
+                     store implementation.
+                     .
                      The library provides an interface for caching, and three implementations:
                      .
                         1. "System.Cache.Impl.Ghc" — the main one based on GHC system;
 
                         2. "System.Cache.Impl.MVar" — implementation based on library functions;
 
                         3. "System.Cache.Impl.NoCache" — implementation that disables caching, but keeps the same interface 
+                     .
+                     If you want to implement your own caching mechanism, or use internal API, you
+                     can refer to the "System.Cache.Internal.Interface" module for an additional documentation.
 extra-source-files:
    CHANGELOG.md
    Readme.md

src/System/Cache/Impl/NoCache.hs

@@ -1,11 +1,16 @@
 {-# LANGUAGE RecursiveDo #-}
+-- | Implementation that provides no caching at all.
+-- Can be useful in order to disable caching without changing
+-- the code at the use sites.
 module System.Cache.Impl.NoCache
   ( new
   ) where
 
 import System.Cache.Internal.Interface
 import System.Clock.Seconds
 
+-- | Creates an implementation that does not cache anything.
+-- All actions runs as-is without locking.
 new :: Config -> IO (Handle a b)
 new Config{..} = do
   pure $ Handle