Use of undefined constant (input) laravel 5

I am junior developer and got stucked with such problem: Laravel brings me back an error: "Use of undefined constant input - assumed 'input'" And I dont understand why: this variable is IN javascript code.

Here it is:

        <div class="form-group">
        {!! Form::label('pac-input', 'Адрес') !!}
        {!! Form::text('pac-input', $meta ? $meta->pac-input:old('pac-input', null), ['class' => 'form-control', 'placeholder' => 'Введите адрес']) !!}
    </div>

My input

var input = (
                document.getElementById('pac-input'));

                var autocomplete = new google.maps.places.Autocomplete(input);
                autocomplete.bindTo('bounds', map);

My JavaScript code (google.maps.api3)

Also got a question: in the source there was a comment after "var input = /** @type {!HTMLInputElement} */( document.getElementById('pac-input'));" - what kind of HTMLInputElement this one wants?

Thanks!

via Chebli Mohamed