According to documentation, in Laravel 5.2 and newer you can use the following code:
@php
{{-- PHP code here --}}
@endphp
Alternatively, you can extend the Blade templating engine as it's described here.
If neither of the above solutions is suitable, you are stuck with the answers given by Armen and by Gonzalo.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…