app/Providers/AppServiceProvider.php
use Illuminate\Support\Facades\Blade;use Illuminate\Support\ServiceProvider; class AppServiceProvider extends ServiceProvider{ // public function register() { Blade::directive('errorClass', function ($field) { $ifStatement = "if(session()->has('errors') && session('errors')->has(${field}))"; return "<?php {$ifStatement} echo 'is-invalid'; ?>"; }); } //}