javascript - How could I debug in nodejs, any tool similar to pdb or pry in Ruby or Python -

i ran script by

node debug sample.js

it stopped @ target position.

somehow, don't know how inspect variables.

for example, want print out variable db , couldn't.

any recommend debugger tool on node.js

thanks

sample.js

// generated coffeescript 1.9.2 (function() {   var mongoclient, print;   print = require('awesome-print');   mongoclient = require('mongodb').mongoclient;   mongoclient.connect('mongodb://localhost:27017/test', function(err, db) {     debugger;     db.command({       listcollections: 1     }, function(err, o) {       debugger;       return print(o["cursor"]);     });   }); }).call(this); 

exception

 20  21 }); debug> print(db) repl:1 print(db) ^ referenceerror: print not defined     @ repl:1:1     @ object.exports.runincontext (vm.js:64:17)     @ interface.controleval (_debugger.js:975:21)     @ bound (domain.js:254:14)     @ replserver.runbound [as eval] (domain.js:267:12)     @ replserver.<anonymous> (repl.js:279:12)     @ replserver.emit (events.js:107:17)     @ replserver.interface._online (readline.js:214:10)     @ replserver.interface._line (readline.js:553:8)     @ replserver.interface._ttywrite (readline.js:830:14) debug> db repl:1 db ^ referenceerror: db not defined     @ repl:1:1     @ object.exports.runincontext (vm.js:64:17)     @ interface.controleval (_debugger.js:975:21)     @ bound (domain.js:254:14)     @ replserver.runbound [as eval] (domain.js:267:12)     @ replserver.<anonymous> (repl.js:279:12)     @ replserver.emit (events.js:107:17)     @ replserver.interface._online (readline.js:214:10) 

you're looking "repl" command in command-line debugger. node-inspector great way hook chrome's awesome devtools node process. can learn how use node-inspector in blog post: lighting javascript debugger