Title: [Plugin: Previous and Next Post in Same Taxonomy] Warning: implode() [function.implode]: Line 68
Last modified: August 20, 2016

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# [Plugin: Previous and Next Post in Same Taxonomy] Warning: implode() [function.implode]: Line 68

 *  Resolved [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/)
 * The plugin is returning this warning:
 * Warning: implode() [function.implode]: Invalid arguments passed in \wp-content\
   plugins\previous-and-next-post-in-same-taxonomy\previous-and-next-post-in-same-
   taxonomy.php on line 68
 * Line 68: $join .= ” AND tt.taxonomy = ‘$taxonomy’ AND tt.term_id IN (” . implode(‘,’,
   $cat_array) . “)”
 * Tested out on a clean version of 3.2.1 using TwentyEleven.
 * The only mod to add custom taxonomies, activated through functions.php. No other
   plugins were enabled.
 * Would love to see this working.
 * [http://wordpress.org/extend/plugins/previous-and-next-post-in-same-taxonomy/](http://wordpress.org/extend/plugins/previous-and-next-post-in-same-taxonomy/)

Viewing 9 replies - 1 through 9 (of 9 total)

 *  Plugin Author [Bill Erickson](https://wordpress.org/support/users/billerickson/)
 * (@billerickson)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2391997)
 * Can you post the code you’re using in your theme? I just tested this plugin yesterday(
   testing all my plugins for 3.3) and it worked fine.
 *  Thread Starter [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392020)
 * I’m sorry, I forgot to mention I am working locally.
 * I just copied and pasted your sample to be sure and changed ‘color’ to my own
   taxonomy and it brings up the error.
 * If I remove it and leave the empty, the error goes and it cycles through the 
   category without a problem.
 * Error
    `<?php be_next_post_link('%link', '%title', true, 'mytaxonomy'); ?>`
 * Fine
    `<?php be_next_post_link('%link', '%title', true, ''); ?>`
 * This is all I’ve added to functions.php
 *     ```
       add_action( 'init', 'my_taxonomies', 0 );
       function my_taxonomies() {
           register_taxonomy( 'my_taxonomies', 'post', array( 'hierarchical' => true, 'label' => 'My Taxonomies', 'query_var' => true, 'rewrite' => true ) );
       }
       ```
   
 * No other changes. Thank you for responding, I really appreciate it.
 *  Plugin Author [Bill Erickson](https://wordpress.org/support/users/billerickson/)
 * (@billerickson)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392040)
 * Your taxonomy is called ‘my_taxonomy’ but you’re putting ‘mytaxonomy’ in the 
   be_next_post_link() function. Can you try it with the proper taxonomy name?
 *  Thread Starter [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392048)
 * Hi Bill,
 * Sorry that was just an example. I’ll double check everything again now.
 *  Thread Starter [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392050)
 * I’m not sure what’s happened but I made these edits and the error went away.
 * Added a custom column function from a plugin into functions.php and
    saw that
   some posts weren’t associated with the taxonomies. Added them in. Changed the
   taxonomy settings from hierachical from true to false and back again. There is
   no error but now but it’s not working the way I understand it would.
 * Say I have two categories: Buy | Sell
 * I also have two custom taxonomies: New | Old
 * My navigation is:
 *     ```
       <?php be_previous_post_link('%link', '%title', true, 'new'); ?>
       <?php be_next_post_link('%link', '%title', true, 'new'); ?>
       ```
   
 * So if I’m the Buy category, looking at a post associated with the taxonomy “New”.
 * I understand that I should be able to continue navigating in the category Buy
   and through posts associated with New.
 * Am I missing something?
 *  Plugin Author [Bill Erickson](https://wordpress.org/support/users/billerickson/)
 * (@billerickson)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392060)
 * I think you’re confused by some terminology. Taxonomy is an organizational structure.‘
   category’ and ‘post_tag’ are built-in taxonomies, but you can add your own. I’m
   going to call the custom taxonomy you make ‘status’.
 * Inside a taxonomy you have taxonomy terms. The ‘category’ taxonomy might have‘
   buy’ and ‘sell’ as terms. The ‘status’ taxonomy might have ‘new’ and ‘old’ as
   terms.
 * The previous_post_link/next_post_link functions in WordPress have an option to
   limit it to the same category. So if you use:
 * `previous_post_link( '%link', '%title', true, '' );`
 * When viewing a post in the Buy category, the previous/next posts would also be
   in the Buy category.
 * I’ve created functions that let you specify a taxonomy other than category. So
   if you use:
 * `be_previous_post_link( '%link', '%title', true, '', 'status' );`
 * When viewing a post in the New term of the Status taxonomy, the previous/next
   posts would also be in the New taxonomy term.
 * This does NOT find intersections between categories and taxonomies (posts in 
   Buy and in New). This only allows the “in same category” option to apply to taxonomies
   other than category.
 *  Thread Starter [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392063)
 * So it basically allows you to specify something other than a standard category,
   but you can’t limit it to both the current category and specify custom taxomony
   with the previous_post_link etc. That’s what I thought the plugin enabled. I 
   think the confusion was more in regards to the in_same_cat parameter rather than
   the taxonomies.
 * I also just realised the navigation I inserted about was wrong. I’d left out 
   fourth parameter ”. I’m still returning the error locally, but I’ll test it out
   live when I get a moment.
 * Thank you again for taking the time to explain it.
 *  Thread Starter [Sina](https://wordpress.org/support/users/tinath/)
 * (@tinath)
 * [14 years, 6 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392109)
 * The error is a user error (mine), but it returns the error if you don’t put the
   correct taxonomy in, I put in the terms and it caused the error. (Refer to Bill’s
   post above regarding.)
 *  [Levdbas](https://wordpress.org/support/users/levdbas/)
 * (@levdbas)
 * [14 years, 2 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392250)
 * Hi, I having a question very related to this problem:
    I got a taxonomy called:
   specialties with terms like online and design. Now I have a posttype cases which
   is linked to this taxonomy. But, as soon as I navigate to a post with **multiple**
   terms something goes wrong. When navigating the Online term everything is fine
   until the post with also the taxonomy Design and all the links after that case
   are in the design term.
 * Am I missing something here? 🙁

Viewing 9 replies - 1 through 9 (of 9 total)

The topic ‘[Plugin: Previous and Next Post in Same Taxonomy] Warning: implode() [
function.implode]: Line 68’ is closed to new replies.

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 * 9 replies
 * 3 participants
 * Last reply from: [Levdbas](https://wordpress.org/support/users/levdbas/)
 * Last activity: [14 years, 2 months ago](https://wordpress.org/support/topic/plugin-previous-and-next-post-in-same-taxonomy-warning-implode-functionimplode-line-68/#post-2392250)
 * Status: resolved