a5bb8817347673d0e9e50acc30b8f68b008e865c.svn-base 1.97 KB
Nested stacktraces for Node.js!
===============================

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With this module, you can wrap a caught exception with extra context
for better debugging.  For example, a network error's stack would normally look
like this:

    Error: connect ECONNREFUSED
        at errnoException (net.js:904:11)
        at Object.afterConnect [as oncomplete] (net.js:895:19)

Using this module, you can wrap the Error with more context to get a stack
that looks like this:

    NestedError: Failed to communicate with localhost:8080
        at Socket.<anonymous> (/Users/mattlavin/Projects/nested-stacks/demo.js:6:18)
        at Socket.EventEmitter.emit (events.js:95:17)
        at net.js:440:14
        at process._tickCallback (node.js:415:13)
    Caused By: Error: connect ECONNREFUSED
        at errnoException (net.js:904:11)
        at Object.afterConnect [as oncomplete] (net.js:895:19)

How to wrap errors
------------------

Here is an example program that uses this module to add more context to errors:

```js
var NestedError = require('nested-error-stacks');
var net = require('net');
    
var client = net.connect({port: 8080});
client.on('error', function (err) {
    var newErr = new NestedError("Failed to communicate with localhost:8080", err);
    console.log(newErr.stack);
});
```

How to inherit
--------------

It is recommended to use explicit names for Error classes. You can do it
like this:

```js
var util = require('util');
var NestedError = require('nested-error-stacks');

function MyError(message, nested) {
    NestedError.call(this, message, nested);
}

util.inherits(MyError, NestedError);
MyError.prototype.name = 'MyError';
```