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| <h1>Node.js v0.10.24 Manual & Documentation</h1> |
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| <a href="index.html" name="toc">Index</a> | |
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| <div id="toc"> |
| <h2>Table of Contents</h2> |
| <ul> |
| <li><a href="#modules_modules">Modules</a><ul> |
| <li><a href="#modules_cycles">Cycles</a></li> |
| <li><a href="#modules_core_modules">Core Modules</a></li> |
| <li><a href="#modules_file_modules">File Modules</a></li> |
| <li><a href="#modules_loading_from_node_modules_folders">Loading from <code>node_modules</code> Folders</a></li> |
| <li><a href="#modules_folders_as_modules">Folders as Modules</a></li> |
| <li><a href="#modules_caching">Caching</a><ul> |
| <li><a href="#modules_module_caching_caveats">Module Caching Caveats</a></li> |
| </ul> |
| </li> |
| <li><a href="#modules_the_module_object">The <code>module</code> Object</a><ul> |
| <li><a href="#modules_module_exports">module.exports</a><ul> |
| <li><a href="#modules_exports_alias">exports alias</a></li> |
| </ul> |
| </li> |
| <li><a href="#modules_module_require_id">module.require(id)</a></li> |
| <li><a href="#modules_module_id">module.id</a></li> |
| <li><a href="#modules_module_filename">module.filename</a></li> |
| <li><a href="#modules_module_loaded">module.loaded</a></li> |
| <li><a href="#modules_module_parent">module.parent</a></li> |
| <li><a href="#modules_module_children">module.children</a></li> |
| </ul> |
| </li> |
| <li><a href="#modules_all_together">All Together...</a></li> |
| <li><a href="#modules_loading_from_the_global_folders">Loading from the global folders</a></li> |
| <li><a href="#modules_accessing_the_main_module">Accessing the main module</a></li> |
| <li><a href="#modules_addenda_package_manager_tips">Addenda: Package Manager Tips</a></li> |
| </ul> |
| </li> |
| </ul> |
| |
| </div> |
| |
| <div id="apicontent"> |
| <h1>Modules<span><a class="mark" href="#modules_modules" id="modules_modules">#</a></span></h1> |
| <pre class="api_stability_5">Stability: 5 - Locked</pre><!--name=module--> |
| |
| <p>Node has a simple module loading system. In Node, files and modules are in |
| one-to-one correspondence. As an example, <code>foo.js</code> loads the module |
| <code>circle.js</code> in the same directory. |
| |
| </p> |
| <p>The contents of <code>foo.js</code>: |
| |
| </p> |
| <pre><code>var circle = require('./circle.js'); |
| console.log( 'The area of a circle of radius 4 is ' |
| + circle.area(4));</code></pre> |
| <p>The contents of <code>circle.js</code>: |
| |
| </p> |
| <pre><code>var PI = Math.PI; |
| |
| exports.area = function (r) { |
| return PI * r * r; |
| }; |
| |
| exports.circumference = function (r) { |
| return 2 * PI * r; |
| };</code></pre> |
| <p>The module <code>circle.js</code> has exported the functions <code>area()</code> and |
| <code>circumference()</code>. To add functions and objects to the root of your module, |
| you can add them to the special <code>exports</code> object. |
| |
| </p> |
| <p>Variables local to the module will be private, as though the module was wrapped |
| in a function. In this example the variable <code>PI</code> is private to <code>circle.js</code>. |
| |
| </p> |
| <p>If you want the root of your module's export to be a function (such as a |
| constructor) or if you want to export a complete object in one assignment |
| instead of building it one property at a time, assign it to <code>module.exports</code> |
| instead of <code>exports</code>. |
| |
| </p> |
| <p>Below, <code>bar.js</code> makes use of the <code>square</code> module, which exports a constructor: |
| |
| </p> |
| <pre><code>var square = require('./square.js'); |
| var mySquare = square(2); |
| console.log('The area of my square is ' + mySquare.area());</code></pre> |
| <p>The <code>square</code> module is defined in <code>square.js</code>: |
| |
| </p> |
| <pre><code>// assigning to exports will not modify module, must use module.exports |
| module.exports = function(width) { |
| return { |
| area: function() { |
| return width * width; |
| } |
| }; |
| }</code></pre> |
| <p>The module system is implemented in the <code>require("module")</code> module. |
| |
| </p> |
| <h2>Cycles<span><a class="mark" href="#modules_cycles" id="modules_cycles">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>When there are circular <code>require()</code> calls, a module might not be |
| done being executed when it is returned. |
| |
| </p> |
| <p>Consider this situation: |
| |
| </p> |
| <p><code>a.js</code>: |
| |
| </p> |
| <pre><code>console.log('a starting'); |
| exports.done = false; |
| var b = require('./b.js'); |
| console.log('in a, b.done = %j', b.done); |
| exports.done = true; |
| console.log('a done');</code></pre> |
| <p><code>b.js</code>: |
| |
| </p> |
| <pre><code>console.log('b starting'); |
| exports.done = false; |
| var a = require('./a.js'); |
| console.log('in b, a.done = %j', a.done); |
| exports.done = true; |
| console.log('b done');</code></pre> |
| <p><code>main.js</code>: |
| |
| </p> |
| <pre><code>console.log('main starting'); |
| var a = require('./a.js'); |
| var b = require('./b.js'); |
| console.log('in main, a.done=%j, b.done=%j', a.done, b.done);</code></pre> |
| <p>When <code>main.js</code> loads <code>a.js</code>, then <code>a.js</code> in turn loads <code>b.js</code>. At that |
| point, <code>b.js</code> tries to load <code>a.js</code>. In order to prevent an infinite |
| loop an <strong>unfinished copy</strong> of the <code>a.js</code> exports object is returned to the |
| <code>b.js</code> module. <code>b.js</code> then finishes loading, and its <code>exports</code> object is |
| provided to the <code>a.js</code> module. |
| |
| </p> |
| <p>By the time <code>main.js</code> has loaded both modules, they're both finished. |
| The output of this program would thus be: |
| |
| </p> |
| <pre><code>$ node main.js |
| main starting |
| a starting |
| b starting |
| in b, a.done = false |
| b done |
| in a, b.done = true |
| a done |
| in main, a.done=true, b.done=true</code></pre> |
| <p>If you have cyclic module dependencies in your program, make sure to |
| plan accordingly. |
| |
| </p> |
| <h2>Core Modules<span><a class="mark" href="#modules_core_modules" id="modules_core_modules">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>Node has several modules compiled into the binary. These modules are |
| described in greater detail elsewhere in this documentation. |
| |
| </p> |
| <p>The core modules are defined in node's source in the <code>lib/</code> folder. |
| |
| </p> |
| <p>Core modules are always preferentially loaded if their identifier is |
| passed to <code>require()</code>. For instance, <code>require('http')</code> will always |
| return the built in HTTP module, even if there is a file by that name. |
| |
| </p> |
| <h2>File Modules<span><a class="mark" href="#modules_file_modules" id="modules_file_modules">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>If the exact filename is not found, then node will attempt to load the |
| required filename with the added extension of <code>.js</code>, <code>.json</code>, and then <code>.node</code>. |
| |
| </p> |
| <p><code>.js</code> files are interpreted as JavaScript text files, and <code>.json</code> files are |
| parsed as JSON text files. <code>.node</code> files are interpreted as compiled addon |
| modules loaded with <code>dlopen</code>. |
| |
| </p> |
| <p>A module prefixed with <code>'/'</code> is an absolute path to the file. For |
| example, <code>require('/home/marco/foo.js')</code> will load the file at |
| <code>/home/marco/foo.js</code>. |
| |
| </p> |
| <p>A module prefixed with <code>'./'</code> is relative to the file calling <code>require()</code>. |
| That is, <code>circle.js</code> must be in the same directory as <code>foo.js</code> for |
| <code>require('./circle')</code> to find it. |
| |
| </p> |
| <p>Without a leading '/' or './' to indicate a file, the module is either a |
| "core module" or is loaded from a <code>node_modules</code> folder. |
| |
| </p> |
| <p>If the given path does not exist, <code>require()</code> will throw an Error with its |
| <code>code</code> property set to <code>'MODULE_NOT_FOUND'</code>. |
| |
| </p> |
| <h2>Loading from <code>node_modules</code> Folders<span><a class="mark" href="#modules_loading_from_node_modules_folders" id="modules_loading_from_node_modules_folders">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>If the module identifier passed to <code>require()</code> is not a native module, |
| and does not begin with <code>'/'</code>, <code>'../'</code>, or <code>'./'</code>, then node starts at the |
| parent directory of the current module, and adds <code>/node_modules</code>, and |
| attempts to load the module from that location. |
| |
| </p> |
| <p>If it is not found there, then it moves to the parent directory, and so |
| on, until the root of the tree is reached. |
| |
| </p> |
| <p>For example, if the file at <code>'/home/ry/projects/foo.js'</code> called |
| <code>require('bar.js')</code>, then node would look in the following locations, in |
| this order: |
| |
| </p> |
| <ul> |
| <li><code>/home/ry/projects/node_modules/bar.js</code></li> |
| <li><code>/home/ry/node_modules/bar.js</code></li> |
| <li><code>/home/node_modules/bar.js</code></li> |
| <li><code>/node_modules/bar.js</code></li> |
| </ul> |
| <p>This allows programs to localize their dependencies, so that they do not |
| clash. |
| |
| </p> |
| <h2>Folders as Modules<span><a class="mark" href="#modules_folders_as_modules" id="modules_folders_as_modules">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>It is convenient to organize programs and libraries into self-contained |
| directories, and then provide a single entry point to that library. |
| There are three ways in which a folder may be passed to <code>require()</code> as |
| an argument. |
| |
| </p> |
| <p>The first is to create a <code>package.json</code> file in the root of the folder, |
| which specifies a <code>main</code> module. An example package.json file might |
| look like this: |
| |
| </p> |
| <pre><code>{ "name" : "some-library", |
| "main" : "./lib/some-library.js" }</code></pre> |
| <p>If this was in a folder at <code>./some-library</code>, then |
| <code>require('./some-library')</code> would attempt to load |
| <code>./some-library/lib/some-library.js</code>. |
| |
| </p> |
| <p>This is the extent of Node's awareness of package.json files. |
| |
| </p> |
| <p>If there is no package.json file present in the directory, then node |
| will attempt to load an <code>index.js</code> or <code>index.node</code> file out of that |
| directory. For example, if there was no package.json file in the above |
| example, then <code>require('./some-library')</code> would attempt to load: |
| |
| </p> |
| <ul> |
| <li><code>./some-library/index.js</code></li> |
| <li><code>./some-library/index.node</code></li> |
| </ul> |
| <h2>Caching<span><a class="mark" href="#modules_caching" id="modules_caching">#</a></span></h2> |
| <!--type=misc--> |
| |
| <p>Modules are cached after the first time they are loaded. This means |
| (among other things) that every call to <code>require('foo')</code> will get |
| exactly the same object returned, if it would resolve to the same file. |
| |
| </p> |
| <p>Multiple calls to <code>require('foo')</code> may not cause the module code to be |
| executed multiple times. This is an important feature. With it, |
| "partially done" objects can be returned, thus allowing transitive |
| dependencies to be loaded even when they would cause cycles. |
| |
| </p> |
| <p>If you want to have a module execute code multiple times, then export a |
| function, and call that function. |
| |
| </p> |
| <h3>Module Caching Caveats<span><a class="mark" href="#modules_module_caching_caveats" id="modules_module_caching_caveats">#</a></span></h3> |
| <!--type=misc--> |
| |
| <p>Modules are cached based on their resolved filename. Since modules may |
| resolve to a different filename based on the location of the calling |
| module (loading from <code>node_modules</code> folders), it is not a <em>guarantee</em> |
| that <code>require('foo')</code> will always return the exact same object, if it |
| would resolve to different files. |
| |
| </p> |
| <h2>The <code>module</code> Object<span><a class="mark" href="#modules_the_module_object" id="modules_the_module_object">#</a></span></h2> |
| <!-- type=var --> |
| <!-- name=module --> |
| |
| <ul> |
| <li>{Object}</li> |
| </ul> |
| <p>In each module, the <code>module</code> free variable is a reference to the object |
| representing the current module. For convenience, <code>module.exports</code> is |
| also accessible via the <code>exports</code> module-global. <code>module</code> isn't actually |
| a global but rather local to each module. |
| |
| </p> |
| <h3>module.exports<span><a class="mark" href="#modules_module_exports" id="modules_module_exports">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">Object</span></li> |
| </div></ul> |
| <p>The <code>module.exports</code> object is created by the Module system. Sometimes this is not |
| acceptable; many want their module to be an instance of some class. To do this |
| assign the desired export object to <code>module.exports</code>. Note that assigning the |
| desired object to <code>exports</code> will simply rebind the local <code>exports</code> variable, |
| which is probably not what you want to do. |
| |
| </p> |
| <p>For example suppose we were making a module called <code>a.js</code> |
| |
| </p> |
| <pre><code>var EventEmitter = require('events').EventEmitter; |
| |
| module.exports = new EventEmitter(); |
| |
| // Do some work, and after some time emit |
| // the 'ready' event from the module itself. |
| setTimeout(function() { |
| module.exports.emit('ready'); |
| }, 1000);</code></pre> |
| <p>Then in another file we could do |
| |
| </p> |
| <pre><code>var a = require('./a'); |
| a.on('ready', function() { |
| console.log('module a is ready'); |
| });</code></pre> |
| <p>Note that assignment to <code>module.exports</code> must be done immediately. It cannot be |
| done in any callbacks. This does not work: |
| |
| </p> |
| <p>x.js: |
| |
| </p> |
| <pre><code>setTimeout(function() { |
| module.exports = { a: "hello" }; |
| }, 0);</code></pre> |
| <p>y.js: |
| |
| </p> |
| <pre><code>var x = require('./x'); |
| console.log(x.a);</code></pre> |
| <h4>exports alias<span><a class="mark" href="#modules_exports_alias" id="modules_exports_alias">#</a></span></h4> |
| <p>The <code>exports</code> variable that is available within a module starts as a reference |
| to <code>module.exports</code>. As with any variable, if you assign a new value to it, it |
| is no longer bound to the previous value. |
| |
| </p> |
| <p>To illustrate the behaviour, imagine this hypothetical implementation of |
| <code>require()</code>: |
| |
| </p> |
| <pre><code>function require(...) { |
| // ... |
| function (module, exports) { |
| // Your module code here |
| exports = some_func; // re-assigns exports, exports is no longer |
| // a shortcut, and nothing is exported. |
| module.exports = some_func; // makes your module export 0 |
| } (module, module.exports); |
| return module; |
| }</code></pre> |
| <p>As a guideline, if the relationship between <code>exports</code> and <code>module.exports</code> |
| seems like magic to you, ignore <code>exports</code> and only use <code>module.exports</code>. |
| |
| </p> |
| <h3>module.require(id)<span><a class="mark" href="#modules_module_require_id" id="modules_module_require_id">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><code>id</code> <span class="type">String</span></li> |
| <li>Return: <span class="type">Object</span> <code>module.exports</code> from the resolved module</li> |
| </div></ul> |
| <p>The <code>module.require</code> method provides a way to load a module as if |
| <code>require()</code> was called from the original module. |
| |
| </p> |
| <p>Note that in order to do this, you must get a reference to the <code>module</code> |
| object. Since <code>require()</code> returns the <code>module.exports</code>, and the <code>module</code> is |
| typically <em>only</em> available within a specific module's code, it must be |
| explicitly exported in order to be used. |
| |
| |
| </p> |
| <h3>module.id<span><a class="mark" href="#modules_module_id" id="modules_module_id">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">String</span></li> |
| </div></ul> |
| <p>The identifier for the module. Typically this is the fully resolved |
| filename. |
| |
| |
| </p> |
| <h3>module.filename<span><a class="mark" href="#modules_module_filename" id="modules_module_filename">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">String</span></li> |
| </div></ul> |
| <p>The fully resolved filename to the module. |
| |
| |
| </p> |
| <h3>module.loaded<span><a class="mark" href="#modules_module_loaded" id="modules_module_loaded">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">Boolean</span></li> |
| </div></ul> |
| <p>Whether or not the module is done loading, or is in the process of |
| loading. |
| |
| |
| </p> |
| <h3>module.parent<span><a class="mark" href="#modules_module_parent" id="modules_module_parent">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">Module Object</span></li> |
| </div></ul> |
| <p>The module that required this one. |
| |
| |
| </p> |
| <h3>module.children<span><a class="mark" href="#modules_module_children" id="modules_module_children">#</a></span></h3> |
| <div class="signature"><ul> |
| <li><span class="type">Array</span></li> |
| </div></ul> |
| <p>The module objects required by this one. |
| |
| |
| |
| </p> |
| <h2>All Together...<span><a class="mark" href="#modules_all_together" id="modules_all_together">#</a></span></h2> |
| <!-- type=misc --> |
| |
| <p>To get the exact filename that will be loaded when <code>require()</code> is called, use |
| the <code>require.resolve()</code> function. |
| |
| </p> |
| <p>Putting together all of the above, here is the high-level algorithm |
| in pseudocode of what require.resolve does: |
| |
| </p> |
| <pre><code>require(X) from module at path Y |
| 1. If X is a core module, |
| a. return the core module |
| b. STOP |
| 2. If X begins with './' or '/' or '../' |
| a. LOAD_AS_FILE(Y + X) |
| b. LOAD_AS_DIRECTORY(Y + X) |
| 3. LOAD_NODE_MODULES(X, dirname(Y)) |
| 4. THROW "not found" |
| |
| LOAD_AS_FILE(X) |
| 1. If X is a file, load X as JavaScript text. STOP |
| 2. If X.js is a file, load X.js as JavaScript text. STOP |
| 3. If X.node is a file, load X.node as binary addon. STOP |
| |
| LOAD_AS_DIRECTORY(X) |
| 1. If X/package.json is a file, |
| a. Parse X/package.json, and look for "main" field. |
| b. let M = X + (json main field) |
| c. LOAD_AS_FILE(M) |
| 2. If X/index.js is a file, load X/index.js as JavaScript text. STOP |
| 3. If X/index.node is a file, load X/index.node as binary addon. STOP |
| |
| LOAD_NODE_MODULES(X, START) |
| 1. let DIRS=NODE_MODULES_PATHS(START) |
| 2. for each DIR in DIRS: |
| a. LOAD_AS_FILE(DIR/X) |
| b. LOAD_AS_DIRECTORY(DIR/X) |
| |
| NODE_MODULES_PATHS(START) |
| 1. let PARTS = path split(START) |
| 2. let ROOT = index of first instance of "node_modules" in PARTS, or 0 |
| 3. let I = count of PARTS - 1 |
| 4. let DIRS = [] |
| 5. while I > ROOT, |
| a. if PARTS[I] = "node_modules" CONTINUE |
| c. DIR = path join(PARTS[0 .. I] + "node_modules") |
| b. DIRS = DIRS + DIR |
| c. let I = I - 1 |
| 6. return DIRS</code></pre> |
| <h2>Loading from the global folders<span><a class="mark" href="#modules_loading_from_the_global_folders" id="modules_loading_from_the_global_folders">#</a></span></h2> |
| <!-- type=misc --> |
| |
| <p>If the <code>NODE_PATH</code> environment variable is set to a colon-delimited list |
| of absolute paths, then node will search those paths for modules if they |
| are not found elsewhere. (Note: On Windows, <code>NODE_PATH</code> is delimited by |
| semicolons instead of colons.) |
| |
| </p> |
| <p>Additionally, node will search in the following locations: |
| |
| </p> |
| <ul> |
| <li>1: <code>$HOME/.node_modules</code></li> |
| <li>2: <code>$HOME/.node_libraries</code></li> |
| <li>3: <code>$PREFIX/lib/node</code></li> |
| </ul> |
| <p>Where <code>$HOME</code> is the user's home directory, and <code>$PREFIX</code> is node's |
| configured <code>node_prefix</code>. |
| |
| </p> |
| <p>These are mostly for historic reasons. You are highly encouraged to |
| place your dependencies locally in <code>node_modules</code> folders. They will be |
| loaded faster, and more reliably. |
| |
| </p> |
| <h2>Accessing the main module<span><a class="mark" href="#modules_accessing_the_main_module" id="modules_accessing_the_main_module">#</a></span></h2> |
| <!-- type=misc --> |
| |
| <p>When a file is run directly from Node, <code>require.main</code> is set to its |
| <code>module</code>. That means that you can determine whether a file has been run |
| directly by testing |
| |
| </p> |
| <pre><code>require.main === module</code></pre> |
| <p>For a file <code>foo.js</code>, this will be <code>true</code> if run via <code>node foo.js</code>, but |
| <code>false</code> if run by <code>require('./foo')</code>. |
| |
| </p> |
| <p>Because <code>module</code> provides a <code>filename</code> property (normally equivalent to |
| <code>__filename</code>), the entry point of the current application can be obtained |
| by checking <code>require.main.filename</code>. |
| |
| </p> |
| <h2>Addenda: Package Manager Tips<span><a class="mark" href="#modules_addenda_package_manager_tips" id="modules_addenda_package_manager_tips">#</a></span></h2> |
| <!-- type=misc --> |
| |
| <p>The semantics of Node's <code>require()</code> function were designed to be general |
| enough to support a number of sane directory structures. Package manager |
| programs such as <code>dpkg</code>, <code>rpm</code>, and <code>npm</code> will hopefully find it possible to |
| build native packages from Node modules without modification. |
| |
| </p> |
| <p>Below we give a suggested directory structure that could work: |
| |
| </p> |
| <p>Let's say that we wanted to have the folder at |
| <code>/usr/lib/node/<some-package>/<some-version></code> hold the contents of a |
| specific version of a package. |
| |
| </p> |
| <p>Packages can depend on one another. In order to install package <code>foo</code>, you |
| may have to install a specific version of package <code>bar</code>. The <code>bar</code> package |
| may itself have dependencies, and in some cases, these dependencies may even |
| collide or form cycles. |
| |
| </p> |
| <p>Since Node looks up the <code>realpath</code> of any modules it loads (that is, |
| resolves symlinks), and then looks for their dependencies in the |
| <code>node_modules</code> folders as described above, this situation is very simple to |
| resolve with the following architecture: |
| |
| </p> |
| <ul> |
| <li><code>/usr/lib/node/foo/1.2.3/</code> - Contents of the <code>foo</code> package, version 1.2.3.</li> |
| <li><code>/usr/lib/node/bar/4.3.2/</code> - Contents of the <code>bar</code> package that <code>foo</code> |
| depends on.</li> |
| <li><code>/usr/lib/node/foo/1.2.3/node_modules/bar</code> - Symbolic link to |
| <code>/usr/lib/node/bar/4.3.2/</code>.</li> |
| <li><code>/usr/lib/node/bar/4.3.2/node_modules/*</code> - Symbolic links to the packages |
| that <code>bar</code> depends on.</li> |
| </ul> |
| <p>Thus, even if a cycle is encountered, or if there are dependency |
| conflicts, every module will be able to get a version of its dependency |
| that it can use. |
| |
| </p> |
| <p>When the code in the <code>foo</code> package does <code>require('bar')</code>, it will get the |
| version that is symlinked into <code>/usr/lib/node/foo/1.2.3/node_modules/bar</code>. |
| Then, when the code in the <code>bar</code> package calls <code>require('quux')</code>, it'll get |
| the version that is symlinked into |
| <code>/usr/lib/node/bar/4.3.2/node_modules/quux</code>. |
| |
| </p> |
| <p>Furthermore, to make the module lookup process even more optimal, rather |
| than putting packages directly in <code>/usr/lib/node</code>, we could put them in |
| <code>/usr/lib/node_modules/<name>/<version></code>. Then node will not bother |
| looking for missing dependencies in <code>/usr/node_modules</code> or <code>/node_modules</code>. |
| |
| </p> |
| <p>In order to make modules available to the node REPL, it might be useful to |
| also add the <code>/usr/lib/node_modules</code> folder to the <code>$NODE_PATH</code> environment |
| variable. Since the module lookups using <code>node_modules</code> folders are all |
| relative, and based on the real path of the files making the calls to |
| <code>require()</code>, the packages themselves can be anywhere. |
| </p> |
| |
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