MODx Revolution: Allows you to "nest" a MODx Revolution Template within another MODx Revolution Template. Requires the use of a Template Switcher plugin

setParentTemplate.snippet.php

<?php
// Requires an Template ID
    if (empty($id))
        return '';
    else
    {//Get the Template
        $parent = $modx->getObject('modTemplate', $id);
    // Must be a valid Template ID
        if (empty($parent))
            return '';
        $parent = $parent->get('content');
    // Adjust the Child Content by removing the call.
        $child = $modx->getObject('modTemplate', $modx->resource->get('template'));
        $child = $child->get('content');
        $sansSnippet = preg_replace("/((?m)(!{0,1}\[\[!inheritTemplate\?{0,1}.{0,}\]\]))/", '', $child);
    // Get the content
        $adjusted = str_replace('[[*content]]', $sansSnippet, $parent);
        $_REQUEST['inherited'] = $adjusted;
        
    // Reset the already processed content
        $output = $adjusted;
        $modx->resource->_output = $output;
    }
    return $output;