coffee/step1_read_print.coffee

   1 readline = require "./node_readline.coffee"
   2 reader = require "./reader.coffee"
   3 printer = require "./printer.coffee"
   4
   5 # read
   6 READ = (str) -> reader.read_str str
   7
   8 # eval
   9 EVAL = (ast, env) -> ast
  10
  11 # print
  12 PRINT = (exp) -> printer._pr_str exp, true
  13
  14 # repl
  15 rep = (str) -> PRINT(EVAL(READ(str), {}))
  16
  17 # repl loop
  18 while (line = readline.readline("user> ")) != null
  19   continue if line == ""
  20   try
  21     console.log rep line
  22   catch exc
  23     continue if exc instanceof reader.BlankException
  24     if exc.stack? and exc.stack.length > 2000
  25       console.log exc.stack.slice(0,1000) + "\n  ..." + exc.stack.slice(-1000)
  26     else if exc.stack? then console.log exc.stack
  27     else                    console.log exc
  28
  29 # vim: ts=2:sw=2