title: Qgis retrieve feature from layer contained in polygon
body: <p>I have a Point_layer and a Polygon_layer;
  I want to edit the field 'name' of the Polygon_layer features with the field 'Name-point' of the Point_layer features only if the point of the Point_layer is contained in the Polygon_layer.
  (I don't have multiple points contained in the polygon layer features)
  I tried to insert this in the Polygon_layer field calculator but it returnes empty fields:</p>
  <pre><code>aggregate(
   layer:= 'Point_layer',
   aggregate:='concatenate',
   expression:= &quot;Name-point&quot;,
   concatenator:=', ',
   filter:=contains($geometry,  geometry(@parent))
   ) 
  </code></pre>
  <p>In my understanding the translation of the expression is:
  take the layer Point_layer
  take the value stored in the field &quot;Name-point&quot;
  Only if the coordinates of Point_layer ($geometry) are contained in the polygon feature (geometry(@parent))
  I'm not sure what
  <code>concatenator:=', '</code> does but I know that it shoudn't break the code.</p>
  <p>where am I wrong?</p>