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<p>Deprecate all the things</p>

<blockquote>
<p>With great modules comes great responsibility; mark things deprecated!</p>
</blockquote>

<h3>Install</h3>

<p>This module is installed directly using <code>npm</code>:</p>

<pre><code>
$ npm install depd
</code></pre>

<p>This module can also be bundled with systems like</p>
<p><a href="http://browserify.org/">Browserify</a> or <a href="https://webpack.github.io/">webpack</a>,</p>
<p>though by default this module will alter it's API to no longer display or</p>
<p>track deprecations.</p>

<h3>API</h3>

<p><!-- eslint-disable no-unused-vars --></p>

<pre><code>
var deprecate = require('depd')('my-module')
</code></pre>

<p>This library allows you to display deprecation messages to your users.</p>
<p>This library goes above and beyond with deprecation warnings by</p>
<p>introspection of the call stack (but only the bits that it is interested</p>
<p>in).</p>

<p>Instead of just warning on the first invocation of a deprecated</p>
<p>function and never again, this module will warn on the first invocation</p>
<p>of a deprecated function per unique call site, making it ideal to alert</p>
<p>users of all deprecated uses across the code base, rather than just</p>
<p>whatever happens to execute first.</p>

<p>The deprecation warnings from this module also include the file and line</p>
<p>information for the call into the module that the deprecated function was</p>
<p>in.</p>

<p><strong>NOTE</strong> this library has a similar interface to the <code>debug</code> module, and</p>
<p>this module uses the calling file to get the boundary for the call stacks,</p>
<p>so you should always create a new <code>deprecate</code> object in each file and not</p>
<p>within some central file.</p>

<h4>depd(namespace)</h4>

<p>Create a new deprecate function that uses the given namespace name in the</p>
<p>messages and will display the call site prior to the stack entering the</p>
<p>file this function was called from. It is highly suggested you use the</p>
<p>name of your module as the namespace.</p>

<h4>deprecate(message)</h4>

<p>Call this function from deprecated code to display a deprecation message.</p>
<p>This message will appear once per unique caller site. Caller site is the</p>
<p>first call site in the stack in a different file from the caller of this</p>
<p>function.</p>

<p>If the message is omitted, a message is generated for you based on the site</p>
<p>of the <code>deprecate()</code> call and will display the name of the function called,</p>
<p>similar to the name displayed in a stack trace.</p>

<h4>deprecate.function(fn, message)</h4>

<p>Call this function to wrap a given function in a deprecation message on any</p>
<p>call to the function. An optional message can be supplied to provide a custom</p>
<p>message.</p>

<h4>deprecate.property(obj, prop, message)</h4>

<p>Call this function to wrap a given property on object in a deprecation message</p>
<p>on any accessing or setting of the property. An optional message can be supplied</p>
<p>to provide a custom message.</p>

<p>The method must be called on the object where the property belongs (not</p>
<p>inherited from the prototype).</p>

<p>If the property is a data descriptor, it will be converted to an accessor</p>
<p>descriptor in order to display the deprecation message.</p>

<h4>process.on('deprecation', fn)</h4>

<p>This module will allow easy capturing of deprecation errors by emitting the</p>
<p>errors as the type "deprecation" on the global <code>process</code>. If there are no</p>
<p>listeners for this type, the errors are written to STDERR as normal, but if</p>
<p>there are any listeners, nothing will be written to STDERR and instead only</p>
<p>emitted. From there, you</p>

<hr>
<p>这个参数你们一般设多少？评论区说说。</p>