tcl/step1_read_print.tcl

   1 source mal_readline.tcl
   2 source types.tcl
   3 source reader.tcl
   4 source printer.tcl
   5
   6 proc READ str {
   7     read_str $str
   8 }
   9
  10 proc EVAL {ast env} {
  11     return $ast
  12 }
  13
  14 proc PRINT exp {
  15     pr_str $exp 1
  16 }
  17
  18 proc REP str {
  19     PRINT [EVAL [READ $str] {}]
  20 }
  21
  22 fconfigure stdout -translation binary
  23
  24 # repl loop
  25 while {true} {
  26     set res [_readline "user> "]
  27     if {[lindex $res 0] == "EOF"} {
  28         break
  29     }
  30     set line [lindex $res 1]
  31     if {$line == ""} {
  32         continue
  33     }
  34     if { [catch { puts [REP $line] } exception] } {
  35         puts "Error: $exception"
  36     }
  37 }
  38 puts ""