nim/printer.nim

   1 import strutils, sequtils, tables, types
   2
   3 proc str_handle(x: string, pr = true): string =
   4   if x.len > 0 and x[0] == '\xff':
   5             result = ":" & x[1 .. x.high]
   6   elif pr:  result = "\"" & x.replace("\\", "\\\\").replace("\"", "\\\"").replace("\n", "\\n") & "\""
   7   else:     result = x
   8
   9 proc pr_str*(m: MalType, pr = true): string =
  10   case m.kind
  11   of Nil:     result = "nil"
  12   of True:    result = "true"
  13   of False:   result = "false"
  14   of Fun:     result = "#<function>"
  15   of MalFun:  result = "#<malfun>"
  16   of Atom:    result = "(atom " & m.val.pr_str & ")"
  17   of Symbol:  result = m.str
  18   of String:  result = m.str.str_handle(pr)
  19   of Number:  result = $m.number
  20   of List:    result = "(" & m.list.mapIt(it.pr_str(pr)).join(" ") & ")"
  21   of Vector:  result = "[" & m.list.mapIt(it.pr_str(pr)).join(" ") & "]"
  22   of HashMap:
  23     result = "{"
  24     for key, val in m.hash_map.pairs:
  25       if result.len > 1: result.add " "
  26       result.add key.str_handle & " " & val.pr_str(pr)
  27     result.add "}"