................................................................................

use>\
    ? let company=Set{ Sequence{'Facebook', 'MenloPark',   'CA','Mark'  },
                       Sequence{'Google',   'MountainView','CA','Sundar'},
                       Sequence{'Microsoft','Redmond',     'WA','Bill'  } } in
      company
.

    Set{Sequence{'Facebook','MenloPark','CA','Mark'},
        Sequence{'Google','MountainView','CA','Sundar'},
        Sequence{'Microsoft','Redmond','WA','Bill'}} : Set(Sequence(String))

use>\
    ? let company=Set{ Sequence{'Facebook', 'MenloPark',   'CA','Mark'  },
                       Sequence{'Google',   'MountainView','CA','Sundar'},
                       Sequence{'Microsoft','Redmond',     'WA','Bill'  } } in
    company->select(C|C->at(3)='CA')->collect(C|C->at(4))
.

    Bag{'Mark','Sundar'} : Bag(String)

use> ?Set{'A','B'}->product(Set{6,7})

     Set{Tuple{first='A',second=6},
         Tuple{first='A',second=7},
         Tuple{first='B',second=6},
         Tuple{first='B',second=7}} : Set(Tuple(first:String,second:Integer))

use> \
     ? let company=Set{ Sequence{'Facebook', 'MenloPark',   'CA','Mark'  },
                        Sequence{'Google',   'MountainView','CA','Sundar'},
                        Sequence{'Microsoft','Redmond',     'WA','Bill'  } } in
     company->product(company)
.

     Set{Tuple{first=Sequence{'Facebook','MenloPark','CA','Mark'},
               second=Sequence{'Facebook','MenloPark','CA','Mark'}},
         Tuple{first=Sequence{'Facebook','MenloPark','CA','Mark'},
               second=Sequence{'Google','MountainView','CA','Sundar'}},
         ...
         Tuple{first=Sequence{'Microsoft','Redmond','WA','Bill'},
               second=Sequence{'Google','MountainView','CA','Sundar'}},
         Tuple{first=Sequence{'Microsoft','Redmond','WA','Bill'},
               second=Sequence{'Microsoft','Redmond','WA','Bill'}}} :
               Set(Tuple(first:Sequence(String),second:Sequence(String)))

use> \
     ? let company=Set{ Sequence{'Facebook', 'MenloPark',   'CA','Mark'  },
                        Sequence{'Google',   'MountainView','CA','Sundar'},
                        Sequence{'Microsoft','Redmond',     'WA','Bill'  } } in
     company->product(company)->size()
.

     9 : Integer

use> \
     ? let company=Set{ Sequence{'Facebook', 'MenloPark',   'CA','Mark'  },
                        Sequence{'Google',   'MountainView','CA','Sundar'},
                        Sequence{'Microsoft','Redmond',     'WA','Bill'  } } in
     company->product(company)->select(T|T.first->at(3)=T.second->at(3) and
                                         T.first->at(4)<T.second->at(4))->
                                collect(T|Sequence{T.first->at(4),T.second->at(4)})
.
     Bag{'Mark','Sundar'} : Bag(String)

........................................................................