Fallback hook for Advanced Custom Fields to prevent missing function errors

acf-fallback.php

<?php

  //http://wordpress.stackexchange.com/questions/243168/providing-fallback-function-and-allow-override-by-plugin


  function acf_fallback(){


    //https://www.advancedcustomfields.com/resources/#functions
    $acf_functions = array(
      'get_field',
      'the_field',
    );
    

    // ACF Plugin fallback

    //!is_plugin_active( 'advanced-custom-fields/acf.php' )
    if( !is_admin() && !function_exists('get_field') ){//!function_exists('get_field')

        function get_field($field = '', $id = false) {
          return false;
        }

        function the_field($field = '', $id = false) {
          return false;
        }

        function have_rows($field = '', $id = false) {
          return false;
        }

        function has_sub_field($field = '', $id = false) {
          return false;
        }

        function get_sub_field($field = '', $id = false) {
          return false;
        }

        function the_sub_field($field = '', $id = false) {
          return false;
        }

    }


  }

  add_action( 'init', 'acf_fallback' );