a domain experiment related to nesting

nestedDomains.js

/*
 * !node nestedDomains
 * ---
 *  error caught at 1: Error: depth reached
 *  error caught at 2: Error: rethrow from depth 1
 *  error caught at 3: Error: rethrow from depth 2
 *  error caught at 4: Error: rethrow from depth 3
 * ---
 *
 *  this makes sense based on the implication from 4th paragraph on implicit binding
 *  http://nodejs.org/api/domain.html#domain_implicit_binding
 *  "If you want to nest Domain objects as children of a parent Domain, then you must explicitly add them."
 *
 * however...
 *
 * !node nestedDomains unsafe
 * ---
 *  ...
 *  ...
 *  error caught at 3: Error: rethrow from depth 4
 *  error caught at 4: Error: rethrow from depth 3
 *  error caught at 3: Error: rethrow from depth 4
 *  error caught at 4: Error: rethrow from depth 3
 *
 *  node.js:0
 *  // Copyright Joyent, Inc. and other Node contributors.
 *  ^
 *  RangeError: Maximum call stack size exceeded
 * ---
 */

var guardian = require('domain');
function nestAndThrow(depth, parentGuardian) {
    if(depth > 0) {
        var g = guardian.create();
        if(parentGuardian) {
            parentGuardian.add(g);
        }
        g.on('error', function(error) {
            console.log("error caught at " + depth + ": " + error);
            if(parentGuardian || process.argv.indexOf('unsafe') !== -1) {
                throw new Error("rethrow from depth " + depth);
            }
        });
        g.run(function() {
            process.nextTick(function() {
                nestAndThrow(depth - 1, g);
            });
        });
    } else {
        process.nextTick(function() {
            throw new Error("depth reached");
        });
    }
}

nestAndThrow(4);