how can be write php inside the laravel's blade page?

i write like this but did not got the output.

 ```@php
    @if(isset($value['0']['cmsg'])) 
    $cmsg = json_decode($value['0']['cmsg']);
    @endif
    @if(isset($value['0']['cmsgerr'])) 
    $cmsgerr = json_decode($value['0']['cmsgerr']);
    @endif
    @endphp```

via Chebli Mohamed