vb/step1_read_print.vb

   1 Imports System
   2 Imports System.IO
   3 Imports Mal
   4 Imports MalVal = Mal.types.MalVal
   5
   6 Namespace Mal
   7     Class step1_read_print
   8         ' read
   9         Shared Function READ(str As String) As MalVal
  10             Return reader.read_str(str)
  11         End Function
  12
  13         ' eval
  14         Shared Function EVAL(ast As MalVal, env As String) As MalVal
  15             Return ast
  16         End Function
  17
  18         ' print
  19         Shared Function PRINT(exp As MalVal) As String
  20             return printer._pr_str(exp, TRUE)
  21         End Function
  22
  23         ' repl
  24         Shared Function REP(str As String) As String
  25             Return PRINT(EVAL(READ(str), ""))
  26         End Function
  27
  28         Shared Function Main As Integer
  29             Dim args As String() = Environment.GetCommandLineArgs()
  30
  31             If args.Length > 1 AndAlso args(1) = "--raw" Then
  32                 Mal.readline.SetMode(Mal.readline.Modes.Raw)
  33             End If
  34
  35             ' repl loop
  36             Dim line As String
  37             Do
  38                 Try
  39                     line = Mal.readline.Readline("user> ")
  40                     If line is Nothing Then
  41                         Exit Do
  42                     End If
  43                     If line = "" Then
  44                         Continue Do
  45                     End If
  46                 Catch e As IOException
  47                     Console.WriteLine("IOException: " & e.Message)
  48                 End Try
  49                 Try
  50                     Console.WriteLine(REP(line))
  51                 Catch e as Exception
  52                     Console.WriteLine("Error: " & e.Message)
  53                     Console.WriteLine(e.StackTrace)
  54                     Continue Do
  55                 End Try
  56             Loop While True
  57         End function
  58     End Class
  59 End Namespace