gistfile1.txt

function csc_forgot_password(){
$username = trim($_POST['csc_forgot_login']);
$user_exists = false;
// First check by username
if ( username_exists( $username ) ){
    $user_exists = true;
    $user = get_user_by('login', $username);
}
elseif(!username_exists($username)) {
	// invalid username
	//trying to see if i can pass a variable from this function to the csc_errors function 
	csc_errors('forgot')->add('username_invalid', __('Invalid username'));
}
/ .. more unnecessary code you don't need to see for these purposes ../ 
} 



// used for tracking error messages
// does putting the variable here collect it from where it was used? 
function csc_errors($form_type){
    static $wp_error; // Will hold global variable safely

    return isset($wp_error) ? $wp_error : ($wp_error = new WP_Error(null, null, null));
}

// displays error messages from form submissions
function csc_show_error_messages() {
global $form_type;
// want to output errors only on the function that triggered the error
	if($codes = csc_errors($form_type)->get_error_codes()) {
		echo '<div class="csc_errors">';
		    // Loop error codes and display errors
		   foreach($codes as $code){
		        $message = csc_errors('forgot')->get_error_message($code);
		        echo '<span class="error"><strong>' . __('Error') . '</strong>: ' . $message . '</span><br/>';
		    }
		echo '</div>';
	}