gistfile1.txt

class Select {
  has $.from;
  has @!columns;

  # We want to be able to chain method calls
  method select(@!columns) { self }

  method Str {
    "SELECT @!columns.map(*.name).join(', ') FROM $!from.name()";
  }
}

class Table {
  has @!columns;
  has $.name;

  method add_columns (*@columns) { @!columns = @columns }

  multi method select($foo) {
    my Select $select .= new;
    return $select.from(self).select(@!columns);
  }

  multi method select(*@columns) { }
}

class Column {
  has Str $.name;
}

use Test;
plan *;

my Table $person = Table.new(name => 'person');
$person.add_columns(
  Column.new( name => 'name' ),
);

my Select $select = $person.select(*);

is(~$select, 'SELECT name FROM person', 'basic SELECT statement');