diff --git a/ethereum-analyzer-cli.cabal b/ethereum-analyzer-cli.cabal
--- a/ethereum-analyzer-cli.cabal
+++ b/ethereum-analyzer-cli.cabal
@@ -1,5 +1,5 @@
 name:                ethereum-analyzer-cli
-version:             3.0.0
+version:             3.1.0
 synopsis:            A CLI frontend for ethereum-analyzer.
 homepage:            https://github.com/zchn/ethereum-analyzer
 license:             Apache-2.0
@@ -21,7 +21,7 @@
 source-repository this
   type:     git
   location: https://github.com/zchn/ethereum-analyzer
-  tag:      v3.0.0
+  tag:      v3.1.0
   subdir:   ethereum-analyzer-cli
 
 library
diff --git a/exec_src/AnalyzeMain.hs b/exec_src/AnalyzeMain.hs
--- a/exec_src/AnalyzeMain.hs
+++ b/exec_src/AnalyzeMain.hs
@@ -40,7 +40,7 @@
 analyze flags@AnalyzeFlags {astJson = theAstJson, debug = debug} = do
   when debug $ putText $ show flags
   content <-
-    if (theAstJson == "" || theAstJson == "-")
+    if theAstJson == "" || theAstJson == "-"
       then getContents
       else readFile $ toS theAstJson
   case decodeContracts content of