lib/pnacl/examples/converter/converter.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org )
   2 #
   3 # Copyright 2014 Johan Kayser <kayser.johan@gmail.com>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #     http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # Example of a currency converter using PNaCl with Nit
  18 #
  19 # First imports the pnacl module
  20 # Then redefines the 'handle_dictionary' method
  21 # Creates a converter and initializes it
  22 # Finally checks for dictionaries
  23
  24 import pnacl
  25
  26 class Converter
  27         super PnaclApp
  28
  29         # We have to redefine the method to do what we want when receiving a dictionary from JS
  30         redef fun handle_dictionary(dictionary: PepperDictionary)
  31         do
  32                 # Getting values from the dictionary
  33                 var from = dictionary["from"]
  34                 var to = dictionary["to"]
  35                 var value = dictionary["value"]
  36
  37                 # If conversion to the same currency return the same value
  38                 if from isa String and to isa String then
  39                         if from == "EUR" and to == "EUR" then
  40                                 if value isa String then
  41                                         var rez = value.to_f
  42                                         var d = new PepperDictionary
  43                                         d["value"] = rez
  44                                         post_dictionary d
  45                                 end
  46                         end
  47                 end
  48                 # If conversion to the same currency return the same value
  49                 if from isa String and to isa String then
  50                         if from == "CAD" and to == "CAD" then
  51                                 if value isa String then
  52                                         var rez = value.to_f
  53                                         var d = new PepperDictionary
  54                                         d["value"] = rez
  55                                         post_dictionary d
  56                                 end
  57                         end
  58                 end
  59                 # If conversion to the same currency return the same value
  60                 if from isa String and to isa String then
  61                         if from == "USD" and to == "USD" then
  62                                 if value isa String then
  63                                         var rez = value.to_f
  64                                         var d = new PepperDictionary
  65                                         d["value"] = rez
  66                                         post_dictionary d
  67                                 end
  68                         end
  69                 end
  70                 # Converts EUR to CAD
  71                 if from == "EUR" and to == "CAD" then
  72                         if value isa String then
  73                                 var rez = (value.to_f * 1.52) # April 30 2014
  74                                 var d = new PepperDictionary
  75                                 d["value"] = rez
  76                                 post_dictionary d
  77                         end
  78                 end
  79                 # Converts EUR to USD
  80                 if from == "EUR" and to == "USD" then
  81                         if value isa String then
  82                                 var rez = (value.to_f * 1.38640) # April 30 2014
  83                                 var d = new PepperDictionary
  84                                 d["value"] = rez
  85                                 post_dictionary d
  86                         end
  87                 end
  88                 # Converts CAD to EUR
  89                 if from == "CAD" and to == "EUR" then
  90                         if value isa String then
  91                                 var rez = (value.to_f * 0.65840) # April 30 2014
  92                                 var d = new PepperDictionary
  93                                 d["value"] = rez
  94                                 post_dictionary d
  95                         end
  96                 end
  97                 # Converts CAD to USD
  98                 if from == "CAD" and to == "USD" then
  99                         if value isa String then
 100                                 var rez = (value.to_f * 0.91240) # April 30 2014
 101                                 var d = new PepperDictionary
 102                                 d["value"] = rez
 103                                 post_dictionary d
 104                         end
 105                 end
 106                 # Converts USD to EUR
 107                 if from == "USD" and to == "EUR" then
 108                         if value isa String then
 109                                 var rez = (value.to_f * 0.721) # April 30 2014
 110                                 var d = new PepperDictionary
 111                                 d["value"] = rez
 112                                 post_dictionary d
 113                         end
 114                 end
 115                 # Converts USD to CAD
 116                 if from == "USD" and to == "CAD" then
 117                         if value isa String then
 118                                 var rez = (value.to_f * 1.095) # April 30 2014
 119                                 var d = new PepperDictionary
 120                                 d["value"] = rez
 121                                 post_dictionary d
 122                         end
 123                 end
 124         end
 125 end
 126
 127 redef fun app do return once new Converter
 128 app.initialize # Needed to correctly set up Nit control over the Pepper API
 129 app.run # Launches an infinite loop in order to check for dictionaries