coffee/node_readline.coffee

   1 # IMPORTANT: choose one
   2 RL_LIB = "libreadline"  # NOTE: libreadline is GPL
   3 #RL_LIB = "libedit"
   4
   5 HISTORY_FILE = require('path').join(process.env.HOME, '.mal-history')
   6
   7 rlwrap = {} # namespace for this module in web context
   8
   9 ffi = require('ffi-napi')
  10 fs = require('fs')
  11
  12 rllib = ffi.Library(RL_LIB, {
  13     'readline': ['string', ['string']],
  14     'add_history': ['int', ['string']]})
  15
  16 rl_history_loaded = false
  17
  18 exports.readline = rlwrap.readline = (prompt = 'user> ') ->
  19   if !rl_history_loaded
  20     rl_history_loaded = true
  21     lines = []
  22     if fs.existsSync(HISTORY_FILE)
  23         lines = fs.readFileSync(HISTORY_FILE).toString().split("\n");
  24
  25     # Max of 2000 lines
  26     lines = lines[Math.max(lines.length - 2000, 0)..]
  27     rllib.add_history(line) for line in lines when line != ""
  28
  29   line = rllib.readline prompt
  30   if line
  31     rllib.add_history line
  32     try
  33       fs.appendFileSync HISTORY_FILE, line + "\n"
  34     catch exc
  35       true
  36
  37   line
  38
  39 # vim: ts=2:sw=2