Scott Reilly

Safely call a function, class method, or object method in a manner that doesn’t generate errors if those plugins cease to exist.
Various helper functions are provided that provide handy variations of this theme:
<ul>
<li><code>_sfc()</code>: Safely call a function and get its return value</li>
<li><code>_sfce()</code>: Safely call a function and echo its return value</li>
<li><code>_sfcf()</code>: Safely call a function; if it doesn’t exist, then a fallback function (if specified) is called</li>
<li><code>_sfcm()</code>: Safely call a function; if it doesn’t exist, then echo a message (if provided)</li>
</ul>
Let’s assume you had something like this in a template:
<pre><code><?php list_cities( 'Texas', 3 ); ?>
</code></pre>
If you deactivated the plugin that provided <code>list_cities()</code>, your site would generate an error when that template is accessed.
You can instead use <code>_sfc()</code>, which is provided by this plugin to call other functions, like so:
<pre><code><?php _sfc( 'list_cities', 'Texas', 3 ); ?>
</code></pre>
That will simply do nothing if the <code>list_cities()</code> function is not available.
If you’d rather display a message when the function does not exist, use <code>_sfcm()</code> instead, like so:
<pre><code><?php _sfcm( 'list_cities', 'The cities listing is temporarily disabled.', 'Texas', 3 ); ?>
</code></pre>
In this case, if <code>list_cities()</code> is not available, the text “The cities listing is temporarily disabled.” will be displayed.
If you’d rather call another function when the function does not exist, use _sfcf() instead, like so:
<pre><code><?php
 function unavailable_function_handler( $function_name ) { echo "The function $function_name is not available."; }
 _sfcf( 'nonexistent_function', 'unavailable_function_handler' );
?>
</code></pre>
In the event you want to safely call a function and echo its value, you can use <code>_sfce()</code> like so:
<pre><code><?php _sfce( 'largest_city', 'Tx' ); ?>
</code></pre>
Which is roughly equivalent to doing :
<pre><code><?php if function_exists( 'largest_city' ) { echo largest_city( 'Tx' ); } ?>
</code></pre>
<h4>Filter invocation method</h4>
To further prevent issues in your code should this plugin itself become deactivated, you can use indirect filter invocation to call the plugin functions. Each function has an associated filter with the same name as the function. Simply use <code>apply_filters()</code> to invoke that function instead of calling the function directly.
E.g. instead of:
<pre><code><?php _sfce( 'some_plugin_function_that_echoes', 'argument' ); ?>
</code></pre>
Do:
<pre><code><?php apply_filters( '_sfce', 'some_plugin_function_that_echoes', 'argument' ); ?>
</code></pre>
If you’re relying on the return value of a function and this plugin gets deactivated, note that the <code>apply_filters()</code> call will return the name of the function you intended to call, so you should check the return value to ensure the function got called.
Instead of:
<pre><code><?php $x = _sfc( 'some_plugin_function', 'argument' ); ?>
</code></pre>
Do:
<pre><code><?php
 $x = apply_filters( '_sfcq', 'some_plugin_function', 'argument' );
 if ( $x !== 'some_plugin_function' ) {
 // Work with the value of $x here.
 } else {
 // The Safe Function Call plugin isn't active.
 $x = 0; // Maybe set the variable to something that makes sense in this scenario.
 }
?>
</code></pre>
Links: <a href="https://coffee2code.com/wp-plugins/safe-function-call/" rel="nofollow ugc">Plugin Homepage</a> | <a href="https://wordpress.org/plugins/safe-function-call/" rel="ugc">Plugin Directory Page</a> | <a href="https://github.com/coffee2code/safe-function-call/" rel="nofollow ugc">GitHub</a> | <a href="https://coffee2code.com" rel="nofollow ugc">Author Homepage</a>
<h3>Developer Documentation</h3>
Developer documentation can be found in <a href="https://github.com/coffee2code/safe-function-call/blob/master/DEVELOPER-DOCS.md" rel="nofollow ugc">DEVELOPER-DOCS.md</a>. That documentation covers the template tags and hooks provided by the plugin.
As an overview, these are the template tags provided by the plugin:
<ul>
<li><code>_sfc()</code> : Safely call a function and get its return value.</li>
<li><code>_sfce()</code> : Safely call a function and echo its sanitized return value.</li>
<li><code>_sfcf()</code> : Safely call a function; if it doesn’t exist, then a fallback function (if specified) is called.</li>
<li><code>_sfcm()</code> : Safely call a function; if it doesn’t exist, then echo a message (if provided).</li>
</ul>
These are the hooks provided by the plugin. They are intended for filter invocation usage rather than typical content filtering.
<ul>
<li><code>_sfc</code> : Filter to safely invoke <code>_sfc()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
<li><code>_sfce</code> : Filter to safely invoke <code>_sfce()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
<li><code>_sfcf</code> : Filter to safely invoke <code>_sfcf()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
<li><code>_sfcm</code> : Filter to safely invoke <code>_sfcm()</code> in such a way that if the plugin were deactivated or deleted, then your calls to the function won’t cause errors in your site.</li>
</ul>

Safe Function Call

Safely and easily call functions that may not be available (such as those provided by a plugin that gets deactivated)

Space X-Chimp

An easy to use, with intuitive interface, WordPress plugin that gives you the ability to easily and safely add your custom code (PHP, HTML, CSS, JavaScript, etc.) to your WordPress website, directly out of the WordPress Admin Area, without the need to have an external editor.
This is a simple and perfect tool to use as your website’s functionality plugin. This is a must have tool for authors and website’s owners. Its purpose is to provide a familiar experience to WordPress users. There is no need for any more editing of the files of your theme or plugins for to add custom code (PHP, HTML, CSS, JavaScript, etc.). Just add your custom code in the field on the plugin page and this plugin will do the rest for you. It will automatically add your custom code to the desired section of your website, without changing any of your theme files and without slowing down your website.
The plugin works completely independently of the theme, so you can use it with any theme. The code you place on the plugin page will be entirely unaffected if you edit the contents of the theme’s files, or even completely change the theme. This is really useful in case of updating theme or plugins, because your custom code would never be overwritten. Your custom code will keep on working, no matter how many times you upgrade or switch your theme and plugins.
On the plugin page you find the code editor powered by CodeMirror. This code editor has options such as syntax highlighting, line numbering, and more. And if you want more options, let us know and we will be happy to add them.
Features
<ul>
<li>Lightweight and fast</li>
<li>Secure code with using clear coding standards</li>
<li>Intuitive interface</li>
<li>Cross browser compatible (work smooth in any modern browser)</li>
<li>Compatible with all WordPress themes</li>
<li>RTL compatible (right to left)</li>
<li>Translation ready</li>
</ul>
Key features include
<ul>
<li>Insert custom PHP/HTML/CSS/JS code into the site</li>
<li>Checks the entered code for fatal errors</li>
<li>Easy disable option for WSOD</li>
<li>Ability to temporarily disable all custom PHP/CSS code</li>
<li>Code syntax highlighting</li>
<li>Line numbering</li>
<li>Active line highlighting</li>
<li>Editor allow for Tab indentation</li>
<li>And much, much more!</li>
</ul>
PRO features include
<ul>
<li>CSS minifier</li>
<li>Manage which HTML/CSS/JS code load on HEAD or FOOTER</li>
<li>Controlling the priority of loading HTML/CSS/JS code</li>
<li>Ability to easily customize the code editor by selecting the desired settings</li>
<li>64 themes for syntax highlighting</li>
<li>Toolbar with useful buttons, such as Undo, Redo, etc.</li>
<li>Ability to use shortcut keys (both Mac and PC) for Search, Replace, etc.</li>
<li>Unlimited number of fields for snippets</li>
<li>Automatic backup of all snippets to a downloadable text file</li>
<li>Separate activation and deactivation of snippets</li>
<li>No ads on the settings page</li>
<li>Well documented</li>
</ul>
<a href="https://www.spacexchimp.com/plugins/custom-code-manager-pro.html" rel="nofollow ugc">Get the PRO version now!</a>
Supported languages
<ul>
<li>PHP</li>
<li>HTML</li>
<li>CSS</li>
<li>JavaScript</li>
</ul>
Translation
This plugin is ready for translation and has already been translated into several languages. But If your language is not available then you can make one. It is also possible that not all existing translations are up-to-date or correct, so you are welcome to make corrections. Many of plugin users would be delighted if you share your translation with the community. Thanks for your contribution!
<ul>
<li>English (default)</li>
<li>Russian (translation by <a href="https://www.instagram.com/milava_kiseleva/" rel="nofollow ugc">Milena Kiseleva</a>)</li>
<li>German (translation by Michael)</li>
<li>Polish (translation by Paweł K.)</li>
<li>Chinese-Taiwan (translation by Gordon Yu)</li>
<li>Spanish (translation by Ramiro Garcés and Patricio Toledo)</li>
<li>Dutch (translation by Peter Leenders)</li>
<li>French (translation by Jean-Michel, Theophil Bethel and Hervé Bouzin)</li>
</ul>
If you want to help translate this plugin, please visit the <a href="https://translate.wordpress.org/projects/wp-plugins/custom-code-manager" rel="nofollow ugc">translation page</a>.
Minimum system requirements:
<ul>
<li><a href="https://wordpress.org">WordPress</a> version 4.9 or higher.</li>
<li><a href="https://secure.php.net" rel="nofollow ugc">PHP</a> version 5.6 or higher.</li>
<li><a href="https://www.mysql.com" rel="nofollow ugc">MySQL</a> version 5.0 or higher.</li>
</ul>
Recommended system requirements:
<ul>
<li><a href="https://wordpress.org">WordPress</a> version 5.0 or higher.</li>
<li><a href="https://secure.php.net" rel="nofollow ugc">PHP</a> version 7.0 or higher.</li>
<li><a href="https://www.mysql.com" rel="nofollow ugc">MySQL</a> version 5.6 or higher.</li>
</ul>
Contribution
Developing plugins is long and tedious work. If you benefit or enjoy this plugin please take the time to:
<ul>
<li><a href="https://www.spacexchimp.com/donate.html" rel="nofollow ugc">Donate</a> to support ongoing development. Your contribution would be greatly appreciated.</li>
<li><a href="https://wordpress.org/support/plugin/custom-code-manager/reviews/#new-post">Rate and Review</a> this plugin.</li>
<li><a href="https://www.spacexchimp.com/contact.html" rel="nofollow ugc">Share with us</a> or view the <a href="https://github.com/ArthurGareginyan/custom-code-manager" rel="nofollow ugc">GitHub Repo</a> if you have any ideas or suggestions to make this plugin better.</li>
</ul>
“Custom Code Manager” is one of the own software projects of <a href="https://www.spacexchimp.com" rel="nofollow ugc">Space X-Chimp</a>.
License
This plugin is licensed under the <a href="http://www.gnu.org/licenses/gpl-3.0.html" rel="nofollow ugc">GNU General Public License, version 3 (GPLv3)</a> and is distributed free of charge. 
Commercial licensing (e.g. for projects that can’t use an open-source license) is available upon request.
Credits
<ul>
<li>The icon of this plugin is a copyrighted image created by the <a href="https://www.spacexchimp.com" rel="nofollow ugc">Space X-Chimp</a> team. (C) All rights reserved.</li>
<li>The banner of this plugin is a copyrighted image created by the <a href="https://www.spacexchimp.com" rel="nofollow ugc">Space X-Chimp</a> team. (C) All rights reserved.</li>
<li>Unless otherwise stated, all images are created by the <a href="https://www.spacexchimp.com" rel="nofollow ugc">Space X-Chimp</a> team and are copyrighted. (C) All rights reserved.</li>
<li><a href="https://codemirror.net/" rel="nofollow ugc">CodeMirror</a> is an open-source project shared under the <a href="https://codemirror.net/LICENSE" rel="nofollow ugc">MIT license</a>.</li>
<li><a href="http://getbootstrap.com" rel="nofollow ugc">Bootstrap</a> by Twitter, Inc. released under the <a href="https://github.com/twbs/bootstrap/blob/master/LICENSE" rel="nofollow ugc">MIT license</a>.</li>
<li><a href="https://github.com/vsn4ik/bootstrap-checkbox" rel="nofollow ugc">Bootstrap-checkbox</a> is a project of <a href="https://github.com/vsn4ik" rel="nofollow ugc">Vasily A.</a>, shared under the <a href="https://github.com/vsn4ik/bootstrap-checkbox/blob/master/LICENSE" rel="nofollow ugc">MIT license</a>.</li>
<li><a href="https://fontawesome.com" rel="nofollow ugc">Font Awesome</a> is an open source-project created by Dave Gandy. Font released under the <a href="http://scripts.sil.org/OFL" rel="nofollow ugc">SIL OFL 1.1 license</a>. Code released under the <a href="http://opensource.org/licenses/mit-license.html" rel="nofollow ugc">MIT License</a>.</li>
</ul>
Links
<ul>
<li><a href="https://www.spacexchimp.com" rel="nofollow ugc">Developer website</a></li>
<li><a href="https://github.com/ArthurGareginyan/custom-code-manager" rel="nofollow ugc">Dedicated plugin page on GitHub</a></li>
<li><a href="https://wordpress.org/plugins/custom-code-manager/">Dedicated plugin page on WordPress.org</a></li>
<li><a href="https://www.spacexchimp.com/plugins/custom-code-manager-pro.html" rel="nofollow ugc">Premium Version</a></li>
</ul>

Custom Code Manager

Easily and safely add your custom code (PHP, HTML, CSS, JavaScript, etc.) to your WordPress website, directly out of the WordPress Admin Area, without …

Safe Function Call vs Custom Code Manager