PHP 7 preg_replace with non-zero array keys for find and replace

issue-3294-example.php

<?php
            $my_find = array ( 0 => '/abc/');
            $my_replace = array( 0 => 'xyz' );
            $my_subject = array( 'abcdefg' );

            echo '<div style="background-color: #ec4;">';
            echo 'find:<pre>'; print_r( $my_find ); echo '</pre><hr>';
            echo 'replace:<pre>'; print_r( $my_replace ); echo '</pre><hr>';
            echo 'subject:<pre>'; print_r( $my_subject ); echo '</pre><hr>';
            echo '</div>';

            $my_subject = preg_replace( $my_find, $my_replace, $my_subject );

            echo '<div style="background-color: #ccc;">';
            echo 'find:<pre>'; print_r( $my_find ); echo '</pre><hr>';
            echo 'replace:<pre>'; print_r( $my_replace ); echo '</pre><hr>';
            echo 'subject:<pre>'; print_r( $my_subject ); echo '</pre><hr>';
            echo '</div>';

            $my_find = array ( 1 => '/abc/');
            $my_replace = array( 1 => 'xyz' );
            $my_subject = array( 'abcdefg' );

            echo '<div style="background-color: #ec4;">';
            echo 'find:<pre>'; print_r( $my_find ); echo '</pre><hr>';
            echo 'replace:<pre>'; print_r( $my_replace ); echo '</pre><hr>';
            echo 'subject:<pre>'; print_r( $my_subject ); echo '</pre><hr>';
            echo '</div>';

            $my_subject = preg_replace( $my_find, $my_replace, $my_subject );

            echo '<div style="background-color: #ccc;">';
            echo 'find:<pre>'; print_r( $my_find ); echo '</pre><hr>';
            echo 'replace:<pre>'; print_r( $my_replace ); echo '</pre><hr>';
            echo 'subject:<pre>'; print_r( $my_subject ); echo '</pre><hr>';
            echo '</div>';