es6 class function

src/solidity/types/Bool.js

@@ -6,24 +6,24 @@ class Bool extends ValueType {
   constructor () {
     super(1, 1, 'bool')
   }
-}
 
-Bool.prototype.decodeFromStorage = function (location, storageContent) {
+  decodeFromStorage (location, storageContent) {
     var value = util.extractHexValue(location, storageContent, this.storageBytes)
     return value !== '00'
-}
+  }
 
-Bool.prototype.decodeFromStack = function (stackDepth, stack, memory) {
+  decodeFromStack (stackDepth, stack, memory) {
     if (stack.length - 1 < stackDepth) {
       return false
     } else {
       return util.extractHexByteSlice(stack[stack.length - 1 - stackDepth], this.storageBytes, 0) !== '00'
     }
-}
+  }
 
-Bool.prototype.decodeFromMemory = function (offset, memory) {
+  decodeFromMemory (offset, memory) {
     var value = memory.substr(offset, 64)
     return util.extractHexByteSlice(value, this.storageBytes, 0) !== '00'
+  }
 }
 
 module.exports = Bool