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) do
  31                 # Getting values from the dictionary
  32                 var from = dictionary["from"]
  33                 var to = dictionary["to"]
  34                 var value = dictionary["value"]
  35
  36                 # If conversion to the same currency return the same value
  37                 if from isa String and to isa String then
  38                         if from == "EUR" and to == "EUR" then
  39                                 if value isa String then
  40                                         var rez = value.to_f
  41                                         var d = new PepperDictionary
  42                                         d["value"] = rez
  43                                         post_dictionary d
  44                                 end
  45                         end
  46                 end
  47                 # If conversion to the same currency return the same value
  48                 if from isa String and to isa String then
  49                         if from == "CAD" and to == "CAD" then
  50                                 if value isa String then
  51                                         var rez = value.to_f
  52                                         var d = new PepperDictionary
  53                                         d["value"] = rez
  54                                         post_dictionary d
  55                                 end
  56                         end
  57                 end
  58                 # If conversion to the same currency return the same value
  59                 if from isa String and to isa String then
  60                         if from == "USD" and to == "USD" then
  61                                 if value isa String then
  62                                         var rez = value.to_f
  63                                         var d = new PepperDictionary
  64                                         d["value"] = rez
  65                                         post_dictionary d
  66                                 end
  67                         end
  68                 end
  69                 # Converts EUR to CAD
  70                 if from == "EUR" and to == "CAD" then
  71                         if value isa String then
  72                                 var rez = (value.to_f * 1.52) # April 30 2014
  73                                 var d = new PepperDictionary
  74                                 d["value"] = rez
  75                                 post_dictionary d
  76                         end
  77                 end
  78                 # Converts EUR to USD
  79                 if from == "EUR" and to == "USD" then
  80                         if value isa String then
  81                                 var rez = (value.to_f * 1.38640) # April 30 2014
  82                                 var d = new PepperDictionary
  83                                 d["value"] = rez
  84                                 post_dictionary d
  85                         end
  86                 end
  87                 # Converts CAD to EUR
  88                 if from == "CAD" and to == "EUR" then
  89                         if value isa String then
  90                                 var rez = (value.to_f * 0.65840) # April 30 2014
  91                                 var d = new PepperDictionary
  92                                 d["value"] = rez
  93                                 post_dictionary d
  94                         end
  95                 end
  96                 # Converts CAD to USD
  97                 if from == "CAD" and to == "USD" then
  98                         if value isa String then
  99                                 var rez = (value.to_f * 0.91240) # April 30 2014
 100                                 var d = new PepperDictionary
 101                                 d["value"] = rez
 102                                 post_dictionary d
 103                         end
 104                 end
 105                 # Converts USD to EUR
 106                 if from == "USD" and to == "EUR" then
 107                         if value isa String then
 108                                 var rez = (value.to_f * 0.721) # April 30 2014
 109                                 var d = new PepperDictionary
 110                                 d["value"] = rez
 111                                 post_dictionary d
 112                         end
 113                 end
 114                 # Converts USD to CAD
 115                 if from == "USD" and to == "CAD" then
 116                         if value isa String then
 117                                 var rez = (value.to_f * 1.095) # April 30 2014
 118                                 var d = new PepperDictionary
 119                                 d["value"] = rez
 120                                 post_dictionary d
 121                         end
 122                 end
 123         end
 124 end
 125
 126 redef fun app do return once new Converter
 127 app.initialize # Needed to correctly set up Nit control over the Pepper API
 128 app.run # Launches an infinite loop in order to check for dictionaries