compact - PHP code example

How to Use the PHP Function Compact to Create Arrays of Variables

PHP has a built-in function that lets you create an array of variables by joining their names and values. This array compact function allows you to simplify your code, improve readability and reduce error rates.

The compact function accepts variable names as its parameters and outputs an associative array with the variable name serving as the key and the current value of that variable in the present scope as the value for that key. This function is especially useful when you need to pass many variables with the same value to a function, but want to avoid multiple for each loops.

This PHP function can also be used in conjunction with slots, a feature that allows you to assign unique values to each variable in an associative array. This way, you can use the same value in multiple places on your site without having to concatenate them all by hand.

In the past, the compact function was fairly forgiving; on string values that could not be resolved to a variable syntax, it would skip them without further warnings. Beginning with PHP 8.1, this behavior has been changed to emit a warning if a non-string or non-array value is passed to the compact function.

This new behavior makes it easier for you to identify where your code is using illegal types and fix them before they cause bugs or errors on production sites. For example, if you are concatenating all your data variable values in for each loops on every page, it will be hard to find where this is occurring and then change it to something more appropriate, like an array.

compact example

        if ( $attachment ) {
            $src = wp_get_attachment_url( $attachment->ID );
        } else {
            $src = $instance['url'];
        }

        echo wp_audio_shortcode(
            array_merge(
                $instance,
                compact( 'src' )
            )
        );
    }

    /** * Enqueue preview scripts. * * These scripts normally are enqueued just-in-time when an audio shortcode is used. * In the customizer, however, widgets can be dynamically added and rendered via * selective refresh, and so it is important to unconditionally enqueue them in * case a widget does get added. * * @since 4.8.0 */

    $post_content = apply_filters( 'phone_content', $content );

    $post_title = xmlrpc_getposttitle( $content );

    if ( '' === trim( $post_title ) ) {
        $post_title = $subject;
    }

    $post_category = array( get_option( 'default_email_category' ) );

    $post_data = compact( 'post_content', 'post_title', 'post_date', 'post_date_gmt', 'post_author', 'post_category', 'post_status' );
    $post_data = wp_slash( $post_data );

    $post_ID = wp_insert_post( $post_data );
    if ( is_wp_error( $post_ID ) ) {
        echo "\n" . $post_ID->get_error_message();
    }

    // The post wasn't inserted or updated, for whatever reason. Better move forward to the next email.     if ( empty( $post_ID ) ) {
        continue;
    }

  /** * Catches and logs errors to $this->errors. * * @param int $errno * The severity level of the error. * @param string $errstr * The error message. */
  public function errorHandler($errno, $errstr) {
    $this->errors[] = compact('errno', 'errstr');
  }

  /** * Asserts that the expected error has been logged. * * @param string $errstr * The error message. * @param int $errno * The severity level of the error. * * @internal */

        if ( is_wp_error( $result ) ) {
            return $result;
        }

        $destination_name = basename( str_replace( $local_destination, '', $destination ) );
        if ( '.' === $destination_name ) {
            $destination_name = '';
        }

        $this->result = compact( 'source', 'source_files', 'destination', 'destination_name', 'local_destination', 'remote_destination', 'clear_destination' );

        /** * Filters the installation response after the installation has finished. * * @since 2.8.0 * * @param bool $response Installation response. * @param array $hook_extra Extra arguments passed to hooked filters. * @param array $result Installation result data. */
        $res = apply_filters( 'upgrader_post_install', true, $args['hook_extra'], $this->result );

    public function _js_vars( $extra_args = array() ) {
        global $tab, $type;
        parent::_js_vars( compact( 'tab', 'type' ) );
    }

    /** * Checks to see if the theme is already installed. * * @since 3.4.0 * * @param stdClass $theme A WordPress.org Theme API object. * @return string Theme status. */
    private function _get_theme_status( $theme ) {

if ( $posts ) {
        foreach ( $posts as $post ) {
            $post_content = addslashes( deslash( $post->post_content ) );
            $post_title   = addslashes( deslash( $post->post_title ) );
            $post_excerpt = addslashes( deslash( $post->post_excerpt ) );
            if ( empty( $post->guid ) ) {
                $guid = get_permalink( $post->ID );
            } else {
                $guid = $post->guid;
            }

            $wpdb->update( $wpdb->posts, compact( 'post_title', 'post_content', 'post_excerpt', 'guid' ), array( 'ID' => $post->ID ) );

        }
    }

    // Remove extraneous backslashes.     $comments = $wpdb->get_results( "SELECT comment_ID, comment_author, comment_content FROM $wpdb->comments" );
    if ( $comments ) {
        foreach ( $comments as $comment ) {
            $comment_content = deslash( $comment->comment_content );
            $comment_author  = deslash( $comment->comment_author );

<?php Akismet::view( 'logo' ); ?> </div> </div> <div class="akismet-lower"> <?php Akismet_Admin::display_status();?> <div class="akismet-boxes"> <?php
            if ( Akismet::predefined_api_key() ) {
                Akismet::view( 'predefined' );
            } elseif ( $akismet_user && in_array( $akismet_user->status, array( 'active', 'active-dunning', 'no-sub', 'missing', 'cancelled', 'suspended' ) ) ) {
                Akismet::view( 'connect-jp', compact( 'akismet_user' ) );
            } else {
                Akismet::view( 'activate' );
            }

            ?> </div> </div> </div>

/** * @param array<string, array<string, mixed>> $deltas */
    public static function fromDelta(string $appName, array $deltas): self
    {
        Feature::triggerDeprecationOrThrow(
            'v6.6.0.0',
            Feature::deprecatedClassMessage(self::class, 'v6.6.0.0', 'Use StoreException::extensionUpdateRequiresConsentAffirmationException instead.')
        );

        return new self('Updating app "{{appName}}" requires a renewed consent affirmation.', compact('appName', 'deltas'));
    }
}

    public function get_inline_script_tag( $handle, $position = 'after' ) {
        $js = $this->get_inline_script_data( $handle, $position );
        if ( empty( $js ) ) {
            return '';
        }

        $id = "{$handle}-js-{$position}";

        return wp_get_inline_script_tag( $js, compact( 'id' ) );
    }

    /** * Localizes a script, only if the script has already been added. * * @since 2.1.0 * * @param string $handle Name of the script to attach data to. * @param string $object_name Name of the variable that will contain the data. * @param array $l10n Array of data to localize. * @return bool True on success, false on failure. */

// "install" & no directory with that slug.             if ( current_user_can( 'install_plugins' ) ) {
                $url = wp_nonce_url( self_admin_url( 'update.php?action=install-plugin&plugin=' . $api->slug ), 'install-plugin_' . $api->slug );
            }
        }
    }
    if ( isset( $_GET['from'] ) ) {
        $url .= '&from=' . urlencode( wp_unslash( $_GET['from'] ) );
    }

    $file = $update_file;
    return compact( 'status', 'url', 'version', 'file' );
}

/** * Displays plugin information in dialog box form. * * @since 2.7.0 * * @global string $tab */
function install_plugin_information() {
    global $tab;

                $abbr_attr = $abbr ? ' abbr="' . esc_attr( $abbr ) . '"' : '';

                $column_display_name = sprintf(
                    '<a href="%1$s">' .
                        '<span>%2$s</span>' .
                        '<span class="sorting-indicators">' .
                            '<span class="sorting-indicator asc" aria-hidden="true"></span>' .
                            '<span class="sorting-indicator desc" aria-hidden="true"></span>' .
                        '</span>' .
                        '%3$s' .
                    '</a>',
                    esc_url( add_query_arg( compact( 'orderby', 'order' ), $current_url ) ),
                    $column_display_name,
                    $order_text
                );
            }

            $tag   = ( 'cb' === $column_key ) ? 'td' : 'th';
            $scope = ( 'th' === $tag ) ? 'scope="col"' : '';
            $id    = $with_id ? "id='$column_key'" : '';

            if ( ! empty( $class ) ) {
                $class = "class='" . implode( ' ', $class ) . "'";
            }

$url = rest_url( 'wp/v2/types/post' );

        // The context for this is editing with the new block editor.         $url = add_query_arg(
            array(
                'context' => 'edit',
            ),
            $url
        );

        $r = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout', 'sslverify' ) );

        if ( is_wp_error( $r ) ) {
            $result['status'] = 'critical';

            $result['label'] = __( 'The REST API encountered an error' );

            $result['description'] .= sprintf(
                '<p>%s</p><p>%s<br>%s</p>',
                __( 'When testing the REST API, an error was encountered:' ),
                sprintf(
                    // translators: %s: The REST API URL.

                    'theme' => $stylesheet,
                    'file'  => $relative_file,
                ),
                admin_url( 'theme-editor.php' )
            )
        );
        exit;
    }
}

$settings = array(
    'codeEditor' => wp_enqueue_code_editor( compact( 'file' ) ),
);
wp_enqueue_script( 'wp-theme-plugin-editor' );
wp_add_inline_script( 'wp-theme-plugin-editor', sprintf( 'jQuery( function( $ ) { wp.themePluginEditor.init( $( "#template" ), %s ); } )', wp_json_encode( $settings ) ) );
wp_add_inline_script( 'wp-theme-plugin-editor', 'wp.themePluginEditor.themeOrPlugin = "theme";' );

require_once ABSPATH . 'wp-admin/admin-header.php';

update_recently_edited( $file );

if ( ! is_file( $file ) ) {
    $error = true;
}

set_time_limit( 5 * MINUTE_IN_SECONDS );
        }

        // Time to wait for loopback requests to finish.         $timeout = 100; // 100 seconds.
        $needle_start = "###### wp_scraping_result_start:$scrape_key ######";
        $needle_end   = "###### wp_scraping_result_end:$scrape_key ######";

        // Attempt loopback request to editor to see if user just whitescreened themselves.         if ( $plugin ) {
            $url = add_query_arg( compact( 'plugin', 'file' ), admin_url( 'plugin-editor.php' ) );
        } elseif ( isset( $stylesheet ) ) {
            $url = add_query_arg(
                array(
                    'theme' => $stylesheet,
                    'file'  => $file,
                ),
                admin_url( 'theme-editor.php' )
            );
        } else {
            $url = admin_url();
        }

continue;
            }

            fseek($stream, $offset);
            $translated = fread($stream, $length);

            if (str_contains($translated, "\000")) {
                $translated = explode("\000", $translated);
            }

            $ids = ['singular' => $singularId, 'plural' => $pluralId];
            $item = compact('ids', 'translated');

            if (!empty($item['ids']['singular'])) {
                $id = $item['ids']['singular'];
                if (isset($item['ids']['plural'])) {
                    $id .= '|'.$item['ids']['plural'];
                }
                $messages[$id] = stripcslashes(implode('|', (array) $item['translated']));
            }
        }

        fclose($stream);