fsharp/printer.fs

   1 module Printer
   2     open System.Text
   3     open Types
   4
   5     type Profile = { Pretty : bool; Separator : string }
   6     let pr_str_profile = { Pretty = true; Separator = " " }
   7     let str_profile = { Pretty = false; Separator = "" }
   8     let prn_profile = { Pretty = true; Separator = " " }
   9     let println_profile = { Pretty = false; Separator = " " }
  10
  11     let print profile nodes =
  12         let acc = StringBuilder()
  13         let appendStr (str : string) = acc.Append(str) |> ignore
  14         let rec pr_node = function
  15             | Nil -> appendStr "nil"
  16             | List(nodes) -> pr_list nodes
  17             | Vector(nodes) -> pr_vector nodes
  18             | Map(map) -> pr_map map
  19             | Symbol(symbol) -> appendStr symbol
  20             | Keyword(keyword) -> appendStr ":"; appendStr keyword
  21             | Number(num) -> acc.Append(num) |> ignore
  22             | String(str) when profile.Pretty -> pr_str_pretty str
  23             | String(str) -> appendStr str
  24             | Bool(true) -> appendStr "true"
  25             | Bool(false) -> appendStr "false"
  26             | Func({ Tag = tag; F = _}) -> pr_func tag
  27
  28         and pr separator prefix node =
  29             appendStr prefix
  30             pr_node node
  31             separator
  32
  33         and std_pr = pr " "
  34
  35         and pr_str_pretty str =
  36             let appendChar = function
  37                 | '\t' -> appendStr "\\t"
  38                 | '\b' -> appendStr "\\b"
  39                 | '\n' -> appendStr "\\n"
  40                 | '\r' -> appendStr "\\r"
  41                 | '\f' -> appendStr "\\f"
  42                 | '\'' -> appendStr "\\'"
  43                 | '"' -> appendStr "\\\""
  44                 | '\\' -> appendStr "\\\\"
  45                 | ch -> acc.Append(ch) |> ignore
  46             appendStr "\""
  47             str |> Seq.iter appendChar
  48             appendStr "\""
  49
  50         and pr_func tag =
  51            sprintf "#<func %d>" tag |> appendStr
  52
  53         and pr_list nodes =
  54             appendStr "("
  55             nodes |> List.fold std_pr  "" |> ignore
  56             appendStr ")"
  57
  58         and pr_vector nodes =
  59             appendStr "["
  60             nodes |> Seq.fold std_pr "" |> ignore
  61             appendStr "]"
  62
  63         and pr_map map =
  64             let pr prefix key value =
  65                 appendStr prefix
  66                 pr_node key
  67                 appendStr " "
  68                 pr_node value
  69                 " "
  70             appendStr "{"
  71             map |> Map.fold pr "" |> ignore
  72             appendStr "}"
  73
  74         nodes |> Seq.fold (pr profile.Separator) "" |> ignore
  75         acc.ToString()
  76
  77     let pr_str : seq<Node> -> string = print pr_str_profile
  78     let str : seq<Node> -> string = print str_profile
  79     let prn : seq<Node> -> string = print prn_profile
  80     let println : seq<Node> -> string = print println_profile