How can the numerical type of a node that can contain different units be changed using @numerical-type: bind
See below, The node '[‘prijs/bewerking’ and ‘aantal’ depends on node ‘eenheid’ and can be in pieces, meter or square meters
'type bewerking': text -> ^ ^ >'model'.'Bewerkingen'[]
'eenheid': text //per meter, m^2 or stuks
'prijs/bewerking': number 'euro' = >'type bewerking'.'prijs'
'aantal': number 'aantal'
'Prijs': number 'euro'= from 'euro' product ( .'aantal' as 'aantal' , .'prijs/bewerking' )