|context> => |context: test map on load>

|list> => range(|number: 1>,|number: 10>)
factors |*> #=> factor |_self>

# map[factors] "" |list>
# does not work as expected on sw load. ie, it does nothing!
# presumably somewhere in process_line it is ignored since it doesn't look like a learn rule.
# 
# but this version does:
|null> => map[factors] "" |list>