hslogger-template (empty) → 0.1

raw patch · 3 files changed

+116/−0 lines, 3 filesdep +basedep +haskell98dep +hsloggersetup-changed

Dependencies added: base, haskell98, hslogger, template-haskell

Files

• Setup.lhs +4/−0
• hslogger-template.cabal +23/−0
• src/System/Log/Logger/TH.hs +89/−0

@@ -0,0 +1,4 @@+#! /usr/bin/env runhaskell++> import Distribution.Simple+> main = defaultMain

@@ -0,0 +1,23 @@+name:     hslogger-template+version:  0.1+synopsis: Automatic generation of hslogger functions+description:+    A function for generating hslogger functions automatically using Template+    Haskell.++license:    PublicDomain+author:     Brian Lewis <brian@lorf.org>, Ian Taylor <ian@lorf.org>+maintainer: Brian Lewis <brian@lorf.org>, Ian Taylor <ian@lorf.org>+category:   Interfaces++cabal-version: >= 1.6+build-type:    Simple++library+  exposed-modules: System.Log.Logger.TH+  build-depends:   base, haskell98, hslogger, template-haskell+  extensions:      TemplateHaskell+  hs-source-dirs:  src+  ghc-options:     -Wall+  if impl(ghc >= 6.8)+    ghc-options: -fwarn-tabs

@@ -0,0 +1,89 @@+-- | This module provides a function that generates hslogger functions+-- automatically using Template Haskell.+module System.Log.Logger.TH (deriveLoggers) where++import qualified Language.Haskell.TH as TH++import qualified System.Log.Logger as HSL++-- | Generate hslogger functions for given priorities.+--+-- Example usage:+--+-- > module Foo.Bar ( ... ) where+-- >+-- > import System.Log.Logger.TH (deriveLoggers)+-- > import qualified System.Log.Logger as HSL+-- >+-- > $(deriveLoggers "HSL" [HSL.DEBUG, HSL.INFO])+--+-- Used this way, @deriveLoggers@ would generate the following functions:+--+-- > info :: String -> IO ()+-- > info s = HSL.infoM "Foo.Bar" ((++) "Foo.Bar: " s)+-- >+-- > debug :: String -> IO ()+-- > debug s = HSL.debugM "Foo.Bar" ((++) "Foo.Bar: " s)+--+-- The other hslogger priorities follow the same pattern.+--+-- So+--+-- > info "hi there"+--+-- would generate the INFO-level log event+--+-- > Foo.Bar: hi there+--+-- Note: "System.Log.Logger" must be imported qualified, and the qualifier must+-- match the qualifier given to @deriveLoggers@.+--+deriveLoggers+  :: String          -- ^ Must match qualifier on import of "System.Log.Logger".+  -> [HSL.Priority]  -- ^ List of priorities for which to generate logging functions.+  -> TH.Q [TH.Dec]+deriveLoggers qualifier priorities =+    fmap TH.loc_module TH.location >>= \moduleName ->+      fmap concat (mapM (deriveLogger qualifier moduleName) priorities)++-- ----------------------------------------++deriveLogger :: String -> String -> HSL.Priority -> TH.Q [TH.Dec]+deriveLogger qualifier moduleName priority = code+  where+    code = do+        sig  <- TH.sigD th_f [t| String -> IO () |]+        body <- TH.funD th_f+                  [ TH.clause [TH.varP th_s]+                    (TH.normalB+                      (TH.appE+                        (TH.appE+                          (TH.varE th_h)+                          (TH.stringE moduleName)+                        )+                        (TH.appE+                          (TH.appE+                            (TH.varE '(++))+                            (TH.litE (TH.stringL (moduleName ++ ": ")))+                          )+                          (TH.varE th_s)+                        )+                      )+                    )+                    []+                  ]+        return [sig, body]+      where+        th_f = TH.mkName functionName+        th_h = TH.mkName (concat [qualifier, ".", functionName, "M"])+        th_s = TH.mkName "s"+        functionName =+          case priority of+            HSL.DEBUG     -> "debug"+            HSL.INFO      -> "info"+            HSL.NOTICE    -> "notice"+            HSL.WARNING   -> "warning"+            HSL.ERROR     -> "error"+            HSL.CRITICAL  -> "critical"+            HSL.ALERT     -> "alert"+            HSL.EMERGENCY -> "emergency"