The relationship method on a undefined method should return an alias of the relation type

[FCO]

model Post {
   has UInt $!author-id is referencing{ Person.id };
   has Person $.author = .^relates: $.author-id;
}

Post.author; # returns a Person alias named author
Post.author.id; # column id from alias author from Person

Post.where: { .author.name eq “FCO” };

[FCO]

if its an Array, its returning a FakeSeq

[FCO]

Not a FakeSeq, but a ResultSeq

[FCO]

model Post {
   has UInt   $!author-id is referencing{ Person.id };
   has Person @.author    is relationship{ .author-id };
}

Post.author;             # returns a Person::ResultSeq :of() an alias named author
Post.author.map( *.id ); # Seq of UInt

Post.all.grep: { .author.name eq “FCO” };

Post.new.author;         # returns a Person::ResultSet

[FCO]

How can I know if I should continue on the ResultSeq chain or if I have to get the values and return a true Seq?

[FCO]

The of of the ResultSeq should define if its only creating the query or if it should run the query and iterate over the results

Person.all                            # returns an Person::ResultSeq (:of(Person))
   .grep({ .name.starts-with("F") })  # adds an "WHERE name like 'F%'" on the query
                                      # and return another Person::ResultSeq
   .flatmap( *.posts )                # now it returns a Post::ResultSeq
                                      # adding a join with the Person
   .grep( *.title.chars == 5 )        # adds "WHERE LENGTH(title) = 5"
   .map( *.body )                     # returns an Red::Default::ResultSeq of Str
                                      # Str doesn't Model, so the next call
                                      # will run the query
   .elems
;

SELECT
   post.body
FROM
   person JOIN post ON(post.author_id = person.id)
WHERE
   person.name like 'F%'
AND
   LENGTH(post.title) = 5
;

[FCO]

It's now possible to call the do-it method on a ResultSeq to return a DoneResultSeq that will run the query on calling iterator method

[FCO]

if you call .Seq on a ResultSeq it will return a Seq that will run the query

[FCO]

but its automatic if you try to consume the seq