lib/csv.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 # CSV output facilities
  16 module csv
  17
  18 # A CSV document representation
  19 class CSVDocument
  20         var header: Array[String] writable = new Array[String]
  21         var lines: Array[Array[String]] = new Array[Array[String]]
  22
  23         fun set_header(values: Object...) do
  24                 header.clear
  25                 for value in values do
  26                         header.add(value.to_s)
  27                 end
  28         end
  29
  30         fun add_line(values: Object...) do
  31                 if values.length != header.length then
  32                         print "CSV error: header declares {header.length} columns, line contains {values.length} values"
  33                         abort
  34                 end
  35                 var line = new Array[String]
  36                 for value in values do
  37                         line.add(value.to_s)
  38                 end
  39                 lines.add(line)
  40         end
  41
  42         redef fun to_s do
  43                 var str = header.join(";") + "\n"
  44                 for line in lines do str += line.join(";") + "\n"
  45                 return str
  46         end
  47
  48         fun save(file: String) do
  49                 var out = new OFStream.open(file)
  50                 out.write(self.to_s)
  51                 out.close
  52         end
  53 end