Inline comment fix and refactoring

.gitignore

@@ -4,3 +4,4 @@ node_modules
 coverage/
 .tern-port
 test/src/**/*.js
+playground

lib/astupdate.js

@@ -6,7 +6,7 @@ const updateComment = require('./updateComment.js')
 
 let patterns = []
 
-const buildExplicitCases = (funcdecl, patterndecls) => {
+const buildExplicitCases = (patterndecls) => {
   const patterncases = []
   let flag = false
   for (const pattern of patterndecls) {
@@ -44,10 +44,10 @@ const buildDefaultCase = (funcdecl) => {
   return defaultcase
 }
 
-const formMultiPatternAst = (funcdecl, patterndecls, ast) => {
+const formMultiPatternAst = (funcdecl, patterndecls) => {
   const funcdeclbody = { type: 'BlockStatement', body: [] }
   const blockstmtbody = { type: 'SwitchStatement', cases: [] }
-  const [cases, flag] = buildExplicitCases(funcdecl, patterndecls)
+  const [cases, flag] = buildExplicitCases(patterndecls)
   const testTempl = funcdecl.declarations[0].init.params[0]
   blockstmtbody.discriminant = testTempl
   if (flag === true) {
@@ -107,30 +107,28 @@ const formFunctionAst = (funcdecl, patterndecls) => {
 const processSubTree = (decl) => {
   if (isArrowFuncDecl(decl)) {
     if (isFunction(decl)) {
-      // funcdeclns
+      // function declarations
       const funcast = formFunctionAst(decl, patterns)
       patterns = []
       return funcast
     } else {
-      // patternfuncdeclns
+      // pattern matched function declarations
       patterns.push(decl)
       return null
     }
   }
   return decl
 }
 
-const updateAst = (mayBeAst) => {
-  const ast = mayBeAst
-  let newbody = []
+const updateAst = (ast) => {
+  let newBody = []
   const declarations = ast.body
-
   declarations.forEach((decl) => {
     const subtree = processSubTree(decl)
-    if (subtree !== null) newbody.push(subtree)
+    if (subtree !== null) newBody.push(subtree)
   })
-  newbody = updateComment(newbody, ast)
-  ast.body = newbody
+  newBody = updateComment(newBody)
+  ast.body = newBody
   return ast
 }