CoffeeScript: add missed node_readline.coffee

1 files changed, 36 insertions, 0 deletions

diff --git a/coffee/node_readline.coffee b/coffee/node_readline.coffee
new file mode 100644
index 0000000..31e5ca0
--- /dev/null
+++ b/coffee/node_readline.coffee
@@ -0,0 +1,36 @@
+# IMPORTANT: choose one
+RL_LIB = "libreadline"  # NOTE: libreadline is GPL
+#RL_LIB = "libedit"
+
+HISTORY_FILE = require('path').join(process.env.HOME, '.mal-history')
+
+rlwrap = {} # namespace for this module in web context
+
+ffi = require('ffi')
+fs = require('fs')
+
+rllib = ffi.Library(RL_LIB, {
+    'readline': ['string', ['string']],
+    'add_history': ['int', ['string']]})
+
+rl_history_loaded = false
+
+exports.readline = rlwrap.readline = (prompt = 'user> ') ->
+  if !rl_history_loaded
+    rl_history_loaded = true
+    lines = []
+    if fs.existsSync(HISTORY_FILE)
+        lines = fs.readFileSync(HISTORY_FILE).toString().split("\n");
+
+    # Max of 2000 lines
+    lines = lines[Math.max(lines.length - 2000, 0)..]
+    rllib.add_history(line) for line in lines when line != ""
+
+  line = rllib.readline prompt
+  if line
+    rllib.add_history line
+    fs.appendFileSync HISTORY_FILE, line + "\n"
+
+  line
+
+# vim: ts=2:sw=2